* [PATCH] c++: non-dependent assignment checking [PR63198, PR18474]
@ 2023-09-17 18:51 Patrick Palka
2023-09-18 3:01 ` Jason Merrill
0 siblings, 1 reply; 4+ messages in thread
From: Patrick Palka @ 2023-09-17 18:51 UTC (permalink / raw)
To: gcc-patches; +Cc: jason, libstdc++, Patrick Palka
Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
trunk? Patch generatde with -w to avoid noisy whitespace changes.
-- >8 --
This patch makes us recognize and check non-dependent simple assigments
ahead of time, like we already do for compound assignments. This means
the templated representation of such assignments will now usually have
an implicit INDIRECT_REF (due to the reference return type), which the
-Wparentheses code needs to handle. As a drive-by improvement, this
patch also makes maybe_convert_cond issue -Wparentheses warnings ahead
of time.
This revealed some libstdc++ tests were attempting to modify a data
member from a uninstantiated const member function; naively fixed by
making the data member mutable.
PR c++/63198
PR c++/18474
gcc/cp/ChangeLog:
* semantics.cc (maybe_convert_cond): Look through implicit
INDIRECT_REF when deciding whether to issue a -Wparentheses
warning, and consider templated assignment expressions as well.
(finish_parenthesized_expr): Look through implicit INDIRECT_REF
when suppressing -Wparentheses warning.
* typeck.cc (build_x_modify_expr): Check simple assignments
ahead time too, not just compound assignments. Give the second
operand of MODOP_EXPR a non-null type so that it's not considered
always instantiation-dependent.
gcc/testsuite/ChangeLog:
* g++.dg/cpp0x/static_assert15.C: Expect diagnostic for
non-constant static_assert condition.
* g++.dg/expr/unary2.C: Remove xfails.
* g++.dg/template/init7.C: Make initializer type-dependent to
preserve intent of test.
* g++.dg/template/recurse3.C: Likewise for the erroneous
statement.
* g++.dg/template/non-dependent26.C: New test.
* g++.dg/warn/Wparentheses-32.C: New test.
libstdc++/ChangeLog:
* testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc:
Make seed_seq::called member mutable.
* testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc:
Likewise.
* testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
Likewise.
* testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc:
Likewise.
* testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc:
Likewise.
* testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc:
Likewise.
* testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
Likewise.
---
gcc/cp/semantics.cc | 17 +++++++----
gcc/cp/typeck.cc | 23 +++++++--------
gcc/testsuite/g++.dg/cpp0x/static_assert15.C | 2 +-
gcc/testsuite/g++.dg/expr/unary2.C | 8 ++----
gcc/testsuite/g++.dg/template/init7.C | 2 +-
.../g++.dg/template/non-dependent26.C | 25 +++++++++++++++++
gcc/testsuite/g++.dg/template/recurse3.C | 8 +++---
gcc/testsuite/g++.dg/warn/Wparentheses-32.C | 28 +++++++++++++++++++
.../discard_block_engine/cons/seed_seq2.cc | 2 +-
.../independent_bits_engine/cons/seed_seq2.cc | 2 +-
.../cons/seed_seq2.cc | 2 +-
.../mersenne_twister_engine/cons/seed_seq2.cc | 2 +-
.../shuffle_order_engine/cons/seed_seq2.cc | 2 +-
.../cons/seed_seq2.cc | 2 +-
.../cons/seed_seq2.cc | 2 +-
15 files changed, 91 insertions(+), 36 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/template/non-dependent26.C
create mode 100644 gcc/testsuite/g++.dg/warn/Wparentheses-32.C
diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 0f7f4e87ae4..b57c1ac868b 100644
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -881,13 +881,17 @@ maybe_convert_cond (tree cond)
/* Do the conversion. */
cond = convert_from_reference (cond);
- if ((TREE_CODE (cond) == MODIFY_EXPR || is_assignment_op_expr_p (cond))
+ tree inner = REFERENCE_REF_P (cond) ? TREE_OPERAND (cond, 0) : cond;
+ if ((TREE_CODE (inner) == MODIFY_EXPR
+ || (TREE_CODE (inner) == MODOP_EXPR
+ && TREE_CODE (TREE_OPERAND (inner, 1)) == NOP_EXPR)
+ || is_assignment_op_expr_p (inner))
&& warn_parentheses
- && !warning_suppressed_p (cond, OPT_Wparentheses)
- && warning_at (cp_expr_loc_or_input_loc (cond),
+ && !warning_suppressed_p (inner, OPT_Wparentheses)
+ && warning_at (cp_expr_loc_or_input_loc (inner),
OPT_Wparentheses, "suggest parentheses around "
"assignment used as truth value"))
- suppress_warning (cond, OPT_Wparentheses);
+ suppress_warning (inner, OPT_Wparentheses);
return condition_conversion (cond);
}
@@ -2155,8 +2159,11 @@ cp_expr
finish_parenthesized_expr (cp_expr expr)
{
if (EXPR_P (expr))
+ {
+ tree inner = REFERENCE_REF_P (expr) ? TREE_OPERAND (expr, 0) : *expr;
/* This inhibits warnings in c_common_truthvalue_conversion. */
- suppress_warning (expr, OPT_Wparentheses);
+ suppress_warning (inner, OPT_Wparentheses);
+ }
if (TREE_CODE (expr) == OFFSET_REF
|| TREE_CODE (expr) == SCOPE_REF)
diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
index 459739d5866..74f5fced060 100644
--- a/gcc/cp/typeck.cc
+++ b/gcc/cp/typeck.cc
@@ -9721,13 +9721,13 @@ build_x_modify_expr (location_t loc, tree lhs, enum tree_code modifycode,
if (lhs == error_mark_node || rhs == error_mark_node)
return cp_expr (error_mark_node, loc);
+ tree op = build_min (modifycode, void_type_node, NULL_TREE, NULL_TREE);
+
if (processing_template_decl)
{
- if (modifycode == NOP_EXPR
- || type_dependent_expression_p (lhs)
+ if (type_dependent_expression_p (lhs)
|| type_dependent_expression_p (rhs))
{
- tree op = build_min_nt_loc (loc, modifycode, NULL_TREE, NULL_TREE);
tree rval = build_min_nt_loc (loc, MODOP_EXPR, lhs, op, rhs);
if (modifycode != NOP_EXPR)
TREE_TYPE (rval)
@@ -9739,15 +9739,15 @@ build_x_modify_expr (location_t loc, tree lhs, enum tree_code modifycode,
rhs = build_non_dependent_expr (rhs);
}
- if (modifycode != NOP_EXPR)
- {
- tree op = build_nt (modifycode, NULL_TREE, NULL_TREE);
- tree rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
+ tree rval;
+ if (modifycode == NOP_EXPR)
+ rval = cp_build_modify_expr (loc, lhs, modifycode, rhs, complain);
+ else
+ rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
lhs, rhs, op, lookups, &overload, complain);
- if (rval)
- {
if (rval == error_mark_node)
- return rval;
+ return error_mark_node;
+ if (modifycode != NOP_EXPR)
suppress_warning (rval /* What warning? */);
if (processing_template_decl)
{
@@ -9760,9 +9760,6 @@ build_x_modify_expr (location_t loc, tree lhs, enum tree_code modifycode,
}
return rval;
}
- }
- return cp_build_modify_expr (loc, lhs, modifycode, rhs, complain);
-}
/* Helper function for get_delta_difference which assumes FROM is a base
class of TO. Returns a delta for the conversion of pointer-to-member
diff --git a/gcc/testsuite/g++.dg/cpp0x/static_assert15.C b/gcc/testsuite/g++.dg/cpp0x/static_assert15.C
index a740f73fd4a..d5f50d07c91 100644
--- a/gcc/testsuite/g++.dg/cpp0x/static_assert15.C
+++ b/gcc/testsuite/g++.dg/cpp0x/static_assert15.C
@@ -5,6 +5,6 @@ template<int x>
struct a {
constexpr void b() {
int c;
- static_assert(c %= 1, "");
+ static_assert(c %= 1, ""); // { dg-error "constant" }
}
};
diff --git a/gcc/testsuite/g++.dg/expr/unary2.C b/gcc/testsuite/g++.dg/expr/unary2.C
index 5962bfe19c9..4db68375944 100644
--- a/gcc/testsuite/g++.dg/expr/unary2.C
+++ b/gcc/testsuite/g++.dg/expr/unary2.C
@@ -1,9 +1,7 @@
+// PR c++/18474
// { dg-do compile }
// Unary plus/minus are not lvalues.
-// In templates we require an instantiation to emit the diagnostic. This
-// is wrong and it is PR 18474.
-
int n;
void f(void)
@@ -15,6 +13,6 @@ void f(void)
template <int>
void g(void)
{
- -n = 0; // { dg-error "lvalue" "" { xfail *-*-* } }
- +n = 0; // { dg-error "lvalue" "" { xfail *-*-* } }
+ -n = 0; // { dg-error "lvalue" "" }
+ +n = 0; // { dg-error "lvalue" "" }
}
diff --git a/gcc/testsuite/g++.dg/template/init7.C b/gcc/testsuite/g++.dg/template/init7.C
index bb26c8f92b5..94fc22f578c 100644
--- a/gcc/testsuite/g++.dg/template/init7.C
+++ b/gcc/testsuite/g++.dg/template/init7.C
@@ -6,4 +6,4 @@ template<typename> struct A
static const int i=0;
};
-template<typename T> const int A<T>::i = 0=0; /* { dg-error "duplicate initialization" } */
+template<typename T> const int A<T>::i = T()=0; /* { dg-error "duplicate initialization" } */
diff --git a/gcc/testsuite/g++.dg/template/non-dependent26.C b/gcc/testsuite/g++.dg/template/non-dependent26.C
new file mode 100644
index 00000000000..1faa39a4b1a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/non-dependent26.C
@@ -0,0 +1,25 @@
+// Verify non-dependent assignment expressions are recognized as such
+// and are checked ahead of time.
+// PR c++/63198
+// { dg-do compile { target c++11 } }
+
+struct X { using t1 = int; };
+struct Y { X operator=(const Y&); } y;
+template<class T> void f1(decltype(y = y)::t1);
+
+int n;
+template<class T> void f2(decltype(n = n)::t1); // { dg-error "not a class" }
+template<class T> void f3(decltype(n += n)::t1); // { dg-error "not a class" }
+
+template<class T>
+void g() {
+ const int n;
+ n = 42; // { dg-error "read-only" }
+
+ const X x;
+ x = {}; // { dg-error "no match" }
+
+ const Y y;
+ y = {}; // { dg-error "no match" }
+ Y{} = X{}; // { dg-error "no match" }
+}
diff --git a/gcc/testsuite/g++.dg/template/recurse3.C b/gcc/testsuite/g++.dg/template/recurse3.C
index f1db7c5cbca..70c6152d063 100644
--- a/gcc/testsuite/g++.dg/template/recurse3.C
+++ b/gcc/testsuite/g++.dg/template/recurse3.C
@@ -1,14 +1,14 @@
// PR c++/44609
// { dg-options -ftemplate-depth=10 }
-template<int N>
+template<class T, int N>
void f()
{
- 0 = 0; // { dg-error "lvalue required" }
- f<N+1>(); // { dg-bogus "instantiation depth" }
+ T(0) = 0; // { dg-error "lvalue required" }
+ f<T, N+1>(); // { dg-bogus "instantiation depth" }
}
int main()
{
- f<0>();
+ f<int, 0>();
}
diff --git a/gcc/testsuite/g++.dg/warn/Wparentheses-32.C b/gcc/testsuite/g++.dg/warn/Wparentheses-32.C
new file mode 100644
index 00000000000..719a9d9e73a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wparentheses-32.C
@@ -0,0 +1,28 @@
+// Verify we issue -Wparentheses warnings at template definition time
+// (for suitable non-dependent expressions).
+// { dg-additional-options "-Wparentheses" }
+
+struct X { operator bool(); };
+struct Y { Y& operator=(const Y&); operator bool(); };
+struct Z { int m; operator bool(); };
+
+template<class T>
+void f() {
+ int n, m;
+ if (n = m) { } // { dg-warning "parentheses" }
+
+ X x1, x2;
+ if (x1 = x2) { } // { dg-warning "parentheses" }
+
+ Y y1, y2;
+ if (y1 = y2) { } // { dg-warning "parentheses" }
+
+ Z z1, z2;
+ if (z1 = z2) { } // { dg-warning "parentheses" }
+
+ bool b;
+ b = m = n; // { dg-warning "parentheses" "" { xfail *-*-* } }
+ b = x1 = x2; // { dg-warning "parentheses" "" { xfail *-*-* } }
+ b = y1 = y2; // { dg-warning "parentheses" "" { xfail *-*-* } }
+ b = z1 = z2; // { dg-warning "parentheses" "" { xfail *-*-* } }
+}
diff --git a/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc
index 720ce96dc28..0d7e667382d 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc
index f378621805f..2ef563038cc 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
index c1cfe9da7fb..071ed75d8d8 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc
index 52476026533..2fb9622fda0 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc
index 1ca783e3044..3fa9c9ad8d3 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc
index 08beb3bcf93..25d19a0ba66 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
index b629053585e..fe798f2f05b 100644
--- a/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
@@ -52,7 +52,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
--
2.42.0.216.gbda494f404
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] c++: non-dependent assignment checking [PR63198, PR18474]
2023-09-17 18:51 [PATCH] c++: non-dependent assignment checking [PR63198, PR18474] Patrick Palka
@ 2023-09-18 3:01 ` Jason Merrill
2023-09-18 13:12 ` Patrick Palka
0 siblings, 1 reply; 4+ messages in thread
From: Jason Merrill @ 2023-09-18 3:01 UTC (permalink / raw)
To: Patrick Palka, gcc-patches; +Cc: libstdc++
On 9/17/23 14:51, Patrick Palka wrote:
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
> trunk? Patch generatde with -w to avoid noisy whitespace changes.
>
> -- >8 --
>
> This patch makes us recognize and check non-dependent simple assigments
> ahead of time, like we already do for compound assignments. This means
> the templated representation of such assignments will now usually have
> an implicit INDIRECT_REF (due to the reference return type), which the
> -Wparentheses code needs to handle. As a drive-by improvement, this
> patch also makes maybe_convert_cond issue -Wparentheses warnings ahead
> of time.
>
> This revealed some libstdc++ tests were attempting to modify a data
> member from a uninstantiated const member function; naively fixed by
> making the data member mutable.
>
> PR c++/63198
> PR c++/18474
>
> gcc/cp/ChangeLog:
>
> * semantics.cc (maybe_convert_cond): Look through implicit
> INDIRECT_REF when deciding whether to issue a -Wparentheses
> warning, and consider templated assignment expressions as well.
> (finish_parenthesized_expr): Look through implicit INDIRECT_REF
> when suppressing -Wparentheses warning.
> * typeck.cc (build_x_modify_expr): Check simple assignments
> ahead time too, not just compound assignments. Give the second
> operand of MODOP_EXPR a non-null type so that it's not considered
> always instantiation-dependent.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/cpp0x/static_assert15.C: Expect diagnostic for
> non-constant static_assert condition.
> * g++.dg/expr/unary2.C: Remove xfails.
> * g++.dg/template/init7.C: Make initializer type-dependent to
> preserve intent of test.
> * g++.dg/template/recurse3.C: Likewise for the erroneous
> statement.
> * g++.dg/template/non-dependent26.C: New test.
> * g++.dg/warn/Wparentheses-32.C: New test.
>
> libstdc++/ChangeLog:
>
> * testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc:
> Make seed_seq::called member mutable.
> * testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc:
> Likewise.
> * testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
> Likewise.
> * testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc:
> Likewise.
> * testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc:
> Likewise.
> * testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc:
> Likewise.
> * testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
> Likewise.
> ---
> gcc/cp/semantics.cc | 17 +++++++----
> gcc/cp/typeck.cc | 23 +++++++--------
> gcc/testsuite/g++.dg/cpp0x/static_assert15.C | 2 +-
> gcc/testsuite/g++.dg/expr/unary2.C | 8 ++----
> gcc/testsuite/g++.dg/template/init7.C | 2 +-
> .../g++.dg/template/non-dependent26.C | 25 +++++++++++++++++
> gcc/testsuite/g++.dg/template/recurse3.C | 8 +++---
> gcc/testsuite/g++.dg/warn/Wparentheses-32.C | 28 +++++++++++++++++++
> .../discard_block_engine/cons/seed_seq2.cc | 2 +-
> .../independent_bits_engine/cons/seed_seq2.cc | 2 +-
> .../cons/seed_seq2.cc | 2 +-
> .../mersenne_twister_engine/cons/seed_seq2.cc | 2 +-
> .../shuffle_order_engine/cons/seed_seq2.cc | 2 +-
> .../cons/seed_seq2.cc | 2 +-
> .../cons/seed_seq2.cc | 2 +-
> 15 files changed, 91 insertions(+), 36 deletions(-)
> create mode 100644 gcc/testsuite/g++.dg/template/non-dependent26.C
> create mode 100644 gcc/testsuite/g++.dg/warn/Wparentheses-32.C
>
> diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
> index 0f7f4e87ae4..b57c1ac868b 100644
> --- a/gcc/cp/semantics.cc
> +++ b/gcc/cp/semantics.cc
> diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
> index 459739d5866..74f5fced060 100644
> --- a/gcc/cp/typeck.cc
> +++ b/gcc/cp/typeck.cc
> @@ -9739,15 +9739,15 @@ build_x_modify_expr (location_t loc, tree lhs, enum tree_code modifycode,
> rhs = build_non_dependent_expr (rhs);
> }
>
> - if (modifycode != NOP_EXPR)
> - {
> - tree op = build_nt (modifycode, NULL_TREE, NULL_TREE);
> - tree rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
> + tree rval;
> + if (modifycode == NOP_EXPR)
> + rval = cp_build_modify_expr (loc, lhs, modifycode, rhs, complain);
> + else
> + rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
> lhs, rhs, op, lookups, &overload, complain);
> - if (rval)
> - {
> if (rval == error_mark_node)
> - return rval;
> + return error_mark_node;
> + if (modifycode != NOP_EXPR)
> suppress_warning (rval /* What warning? */);
Did you try disabling this to see if it's still needed?
Jason
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] c++: non-dependent assignment checking [PR63198, PR18474]
2023-09-18 3:01 ` Jason Merrill
@ 2023-09-18 13:12 ` Patrick Palka
2023-09-18 13:33 ` Jason Merrill
0 siblings, 1 reply; 4+ messages in thread
From: Patrick Palka @ 2023-09-18 13:12 UTC (permalink / raw)
To: Jason Merrill; +Cc: Patrick Palka, gcc-patches, libstdc++
On Sun, 17 Sep 2023, Jason Merrill wrote:
> On 9/17/23 14:51, Patrick Palka wrote:
> > Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
> > trunk? Patch generatde with -w to avoid noisy whitespace changes.
> >
> > -- >8 --
> >
> > This patch makes us recognize and check non-dependent simple assigments
> > ahead of time, like we already do for compound assignments. This means
> > the templated representation of such assignments will now usually have
> > an implicit INDIRECT_REF (due to the reference return type), which the
> > -Wparentheses code needs to handle. As a drive-by improvement, this
> > patch also makes maybe_convert_cond issue -Wparentheses warnings ahead
> > of time.
> >
> > This revealed some libstdc++ tests were attempting to modify a data
> > member from a uninstantiated const member function; naively fixed by
> > making the data member mutable.
> >
> > PR c++/63198
> > PR c++/18474
> >
> > gcc/cp/ChangeLog:
> >
> > * semantics.cc (maybe_convert_cond): Look through implicit
> > INDIRECT_REF when deciding whether to issue a -Wparentheses
> > warning, and consider templated assignment expressions as well.
> > (finish_parenthesized_expr): Look through implicit INDIRECT_REF
> > when suppressing -Wparentheses warning.
> > * typeck.cc (build_x_modify_expr): Check simple assignments
> > ahead time too, not just compound assignments. Give the second
> > operand of MODOP_EXPR a non-null type so that it's not considered
> > always instantiation-dependent.
> >
> > gcc/testsuite/ChangeLog:
> >
> > * g++.dg/cpp0x/static_assert15.C: Expect diagnostic for
> > non-constant static_assert condition.
> > * g++.dg/expr/unary2.C: Remove xfails.
> > * g++.dg/template/init7.C: Make initializer type-dependent to
> > preserve intent of test.
> > * g++.dg/template/recurse3.C: Likewise for the erroneous
> > statement.
> > * g++.dg/template/non-dependent26.C: New test.
> > * g++.dg/warn/Wparentheses-32.C: New test.
> >
> > libstdc++/ChangeLog:
> >
> > * testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc:
> > Make seed_seq::called member mutable.
> > *
> > testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc:
> > Likewise.
> > *
> > testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
> > Likewise.
> > *
> > testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc:
> > Likewise.
> > * testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc:
> > Likewise.
> > *
> > testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc:
> > Likewise.
> > *
> > testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
> > Likewise.
> > ---
> > gcc/cp/semantics.cc | 17 +++++++----
> > gcc/cp/typeck.cc | 23 +++++++--------
> > gcc/testsuite/g++.dg/cpp0x/static_assert15.C | 2 +-
> > gcc/testsuite/g++.dg/expr/unary2.C | 8 ++----
> > gcc/testsuite/g++.dg/template/init7.C | 2 +-
> > .../g++.dg/template/non-dependent26.C | 25 +++++++++++++++++
> > gcc/testsuite/g++.dg/template/recurse3.C | 8 +++---
> > gcc/testsuite/g++.dg/warn/Wparentheses-32.C | 28 +++++++++++++++++++
> > .../discard_block_engine/cons/seed_seq2.cc | 2 +-
> > .../independent_bits_engine/cons/seed_seq2.cc | 2 +-
> > .../cons/seed_seq2.cc | 2 +-
> > .../mersenne_twister_engine/cons/seed_seq2.cc | 2 +-
> > .../shuffle_order_engine/cons/seed_seq2.cc | 2 +-
> > .../cons/seed_seq2.cc | 2 +-
> > .../cons/seed_seq2.cc | 2 +-
> > 15 files changed, 91 insertions(+), 36 deletions(-)
> > create mode 100644 gcc/testsuite/g++.dg/template/non-dependent26.C
> > create mode 100644 gcc/testsuite/g++.dg/warn/Wparentheses-32.C
> >
> > diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
> > index 0f7f4e87ae4..b57c1ac868b 100644
> > --- a/gcc/cp/semantics.cc
> > +++ b/gcc/cp/semantics.cc
> > diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
> > index 459739d5866..74f5fced060 100644
> > --- a/gcc/cp/typeck.cc
> > +++ b/gcc/cp/typeck.cc
> > @@ -9739,15 +9739,15 @@ build_x_modify_expr (location_t loc, tree lhs, enum
> > tree_code modifycode,
> > rhs = build_non_dependent_expr (rhs);
> > }
> > - if (modifycode != NOP_EXPR)
> > - {
> > - tree op = build_nt (modifycode, NULL_TREE, NULL_TREE);
> > - tree rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
> > + tree rval;
> > + if (modifycode == NOP_EXPR)
> > + rval = cp_build_modify_expr (loc, lhs, modifycode, rhs, complain);
> > + else
> > + rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
> > lhs, rhs, op, lookups, &overload, complain);
> > - if (rval)
> > - {
> > if (rval == error_mark_node)
> > - return rval;
> > + return error_mark_node;
> > + if (modifycode != NOP_EXPR)
> > suppress_warning (rval /* What warning? */);
>
> Did you try disabling this to see if it's still needed?
Looks like it's not needed as far as bootstrap + regtest is concerned.
FWIW this line originally was added in
https://gcc.gnu.org/pipermail/gcc-patches/2004-July/144621.html
to suppress -Wparentheses warnings for non-templated compound assignment
operator expressions.
Here's a patch that also gets rid of that suppress_warning call:
-- >8 --
Subject: [PATCH] c++: non-dependent assignment checking [PR63198, PR18474]
PR c++/63198
PR c++/18474
gcc/cp/ChangeLog:
* semantics.cc (maybe_convert_cond): Look through implicit
INDIRECT_REF when deciding whether to issue a -Wparentheses
warning, and consider templated assignment expressions as well.
(finish_parenthesized_expr): Look through implicit INDIRECT_REF
when suppressing -Wparentheses warning.
* typeck.cc (build_x_modify_expr): Check simple assignments
ahead time too, not just compound assignments. Give the second
operand of MODOP_EXPR a non-null type so that it's not considered
always instantiation-dependent. Don't call suppress_warning.
gcc/testsuite/ChangeLog:
* g++.dg/cpp0x/static_assert15.C: Expect diagnostic for
non-constant static_assert condition.
* g++.dg/expr/unary2.C: Remove xfails.
* g++.dg/template/init7.C: Make initializer type-dependent to
preserve intent of test.
* g++.dg/template/recurse3.C: Likewise for the erroneous
statement.
* g++.dg/template/non-dependent26.C: New test.
* g++.dg/warn/Wparentheses-32.C: New test.
libstdc++/ChangeLog:
* testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc:
Make data member seed_seq::called mutable.
* testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc:
Likewise.
* testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
Likewise.
* testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc:
Likewise.
* testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc:
Likewise.
* testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc:
Likewise.
* testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
Likewise.
---
gcc/cp/semantics.cc | 19 ++++++---
gcc/cp/typeck.cc | 41 ++++++++-----------
gcc/testsuite/g++.dg/cpp0x/static_assert15.C | 2 +-
gcc/testsuite/g++.dg/expr/unary2.C | 8 ++--
gcc/testsuite/g++.dg/template/init7.C | 2 +-
.../g++.dg/template/non-dependent26.C | 25 +++++++++++
gcc/testsuite/g++.dg/template/recurse3.C | 8 ++--
gcc/testsuite/g++.dg/warn/Wparentheses-32.C | 28 +++++++++++++
.../discard_block_engine/cons/seed_seq2.cc | 2 +-
.../independent_bits_engine/cons/seed_seq2.cc | 2 +-
.../cons/seed_seq2.cc | 2 +-
.../mersenne_twister_engine/cons/seed_seq2.cc | 2 +-
.../shuffle_order_engine/cons/seed_seq2.cc | 2 +-
.../cons/seed_seq2.cc | 2 +-
.../cons/seed_seq2.cc | 2 +-
15 files changed, 100 insertions(+), 47 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/template/non-dependent26.C
create mode 100644 gcc/testsuite/g++.dg/warn/Wparentheses-32.C
diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 0f7f4e87ae4..4109ac33654 100644
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -881,13 +881,17 @@ maybe_convert_cond (tree cond)
/* Do the conversion. */
cond = convert_from_reference (cond);
- if ((TREE_CODE (cond) == MODIFY_EXPR || is_assignment_op_expr_p (cond))
+ tree inner = REFERENCE_REF_P (cond) ? TREE_OPERAND (cond, 0) : cond;
+ if ((TREE_CODE (inner) == MODIFY_EXPR
+ || (TREE_CODE (inner) == MODOP_EXPR
+ && TREE_CODE (TREE_OPERAND (inner, 1)) == NOP_EXPR)
+ || is_assignment_op_expr_p (inner))
&& warn_parentheses
- && !warning_suppressed_p (cond, OPT_Wparentheses)
- && warning_at (cp_expr_loc_or_input_loc (cond),
+ && !warning_suppressed_p (inner, OPT_Wparentheses)
+ && warning_at (cp_expr_loc_or_input_loc (inner),
OPT_Wparentheses, "suggest parentheses around "
"assignment used as truth value"))
- suppress_warning (cond, OPT_Wparentheses);
+ suppress_warning (inner, OPT_Wparentheses);
return condition_conversion (cond);
}
@@ -2155,8 +2159,11 @@ cp_expr
finish_parenthesized_expr (cp_expr expr)
{
if (EXPR_P (expr))
- /* This inhibits warnings in c_common_truthvalue_conversion. */
- suppress_warning (expr, OPT_Wparentheses);
+ {
+ /* This inhibits warnings in c_common_truthvalue_conversion. */
+ tree inner = REFERENCE_REF_P (expr) ? TREE_OPERAND (expr, 0) : *expr;
+ suppress_warning (inner, OPT_Wparentheses);
+ }
if (TREE_CODE (expr) == OFFSET_REF
|| TREE_CODE (expr) == SCOPE_REF)
diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
index 459739d5866..8132bd7fccc 100644
--- a/gcc/cp/typeck.cc
+++ b/gcc/cp/typeck.cc
@@ -9721,13 +9721,13 @@ build_x_modify_expr (location_t loc, tree lhs, enum tree_code modifycode,
if (lhs == error_mark_node || rhs == error_mark_node)
return cp_expr (error_mark_node, loc);
+ tree op = build_min (modifycode, void_type_node, NULL_TREE, NULL_TREE);
+
if (processing_template_decl)
{
- if (modifycode == NOP_EXPR
- || type_dependent_expression_p (lhs)
+ if (type_dependent_expression_p (lhs)
|| type_dependent_expression_p (rhs))
{
- tree op = build_min_nt_loc (loc, modifycode, NULL_TREE, NULL_TREE);
tree rval = build_min_nt_loc (loc, MODOP_EXPR, lhs, op, rhs);
if (modifycode != NOP_EXPR)
TREE_TYPE (rval)
@@ -9739,29 +9739,24 @@ build_x_modify_expr (location_t loc, tree lhs, enum tree_code modifycode,
rhs = build_non_dependent_expr (rhs);
}
- if (modifycode != NOP_EXPR)
+ tree rval;
+ if (modifycode == NOP_EXPR)
+ rval = cp_build_modify_expr (loc, lhs, modifycode, rhs, complain);
+ else
+ rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
+ lhs, rhs, op, lookups, &overload, complain);
+ if (rval == error_mark_node)
+ return error_mark_node;
+ if (processing_template_decl)
{
- tree op = build_nt (modifycode, NULL_TREE, NULL_TREE);
- tree rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
- lhs, rhs, op, lookups, &overload, complain);
- if (rval)
- {
- if (rval == error_mark_node)
- return rval;
- suppress_warning (rval /* What warning? */);
- if (processing_template_decl)
- {
- if (overload != NULL_TREE)
- return (build_min_non_dep_op_overload
- (MODIFY_EXPR, rval, overload, orig_lhs, orig_rhs));
+ if (overload != NULL_TREE)
+ return (build_min_non_dep_op_overload
+ (MODIFY_EXPR, rval, overload, orig_lhs, orig_rhs));
- return (build_min_non_dep
- (MODOP_EXPR, rval, orig_lhs, op, orig_rhs));
- }
- return rval;
- }
+ return (build_min_non_dep
+ (MODOP_EXPR, rval, orig_lhs, op, orig_rhs));
}
- return cp_build_modify_expr (loc, lhs, modifycode, rhs, complain);
+ return rval;
}
/* Helper function for get_delta_difference which assumes FROM is a base
diff --git a/gcc/testsuite/g++.dg/cpp0x/static_assert15.C b/gcc/testsuite/g++.dg/cpp0x/static_assert15.C
index a740f73fd4a..d5f50d07c91 100644
--- a/gcc/testsuite/g++.dg/cpp0x/static_assert15.C
+++ b/gcc/testsuite/g++.dg/cpp0x/static_assert15.C
@@ -5,6 +5,6 @@ template<int x>
struct a {
constexpr void b() {
int c;
- static_assert(c %= 1, "");
+ static_assert(c %= 1, ""); // { dg-error "constant" }
}
};
diff --git a/gcc/testsuite/g++.dg/expr/unary2.C b/gcc/testsuite/g++.dg/expr/unary2.C
index 5962bfe19c9..4db68375944 100644
--- a/gcc/testsuite/g++.dg/expr/unary2.C
+++ b/gcc/testsuite/g++.dg/expr/unary2.C
@@ -1,9 +1,7 @@
+// PR c++/18474
// { dg-do compile }
// Unary plus/minus are not lvalues.
-// In templates we require an instantiation to emit the diagnostic. This
-// is wrong and it is PR 18474.
-
int n;
void f(void)
@@ -15,6 +13,6 @@ void f(void)
template <int>
void g(void)
{
- -n = 0; // { dg-error "lvalue" "" { xfail *-*-* } }
- +n = 0; // { dg-error "lvalue" "" { xfail *-*-* } }
+ -n = 0; // { dg-error "lvalue" "" }
+ +n = 0; // { dg-error "lvalue" "" }
}
diff --git a/gcc/testsuite/g++.dg/template/init7.C b/gcc/testsuite/g++.dg/template/init7.C
index bb26c8f92b5..94fc22f578c 100644
--- a/gcc/testsuite/g++.dg/template/init7.C
+++ b/gcc/testsuite/g++.dg/template/init7.C
@@ -6,4 +6,4 @@ template<typename> struct A
static const int i=0;
};
-template<typename T> const int A<T>::i = 0=0; /* { dg-error "duplicate initialization" } */
+template<typename T> const int A<T>::i = T()=0; /* { dg-error "duplicate initialization" } */
diff --git a/gcc/testsuite/g++.dg/template/non-dependent26.C b/gcc/testsuite/g++.dg/template/non-dependent26.C
new file mode 100644
index 00000000000..1faa39a4b1a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/non-dependent26.C
@@ -0,0 +1,25 @@
+// Verify non-dependent assignment expressions are recognized as such
+// and are checked ahead of time.
+// PR c++/63198
+// { dg-do compile { target c++11 } }
+
+struct X { using t1 = int; };
+struct Y { X operator=(const Y&); } y;
+template<class T> void f1(decltype(y = y)::t1);
+
+int n;
+template<class T> void f2(decltype(n = n)::t1); // { dg-error "not a class" }
+template<class T> void f3(decltype(n += n)::t1); // { dg-error "not a class" }
+
+template<class T>
+void g() {
+ const int n;
+ n = 42; // { dg-error "read-only" }
+
+ const X x;
+ x = {}; // { dg-error "no match" }
+
+ const Y y;
+ y = {}; // { dg-error "no match" }
+ Y{} = X{}; // { dg-error "no match" }
+}
diff --git a/gcc/testsuite/g++.dg/template/recurse3.C b/gcc/testsuite/g++.dg/template/recurse3.C
index f1db7c5cbca..70c6152d063 100644
--- a/gcc/testsuite/g++.dg/template/recurse3.C
+++ b/gcc/testsuite/g++.dg/template/recurse3.C
@@ -1,14 +1,14 @@
// PR c++/44609
// { dg-options -ftemplate-depth=10 }
-template<int N>
+template<class T, int N>
void f()
{
- 0 = 0; // { dg-error "lvalue required" }
- f<N+1>(); // { dg-bogus "instantiation depth" }
+ T(0) = 0; // { dg-error "lvalue required" }
+ f<T, N+1>(); // { dg-bogus "instantiation depth" }
}
int main()
{
- f<0>();
+ f<int, 0>();
}
diff --git a/gcc/testsuite/g++.dg/warn/Wparentheses-32.C b/gcc/testsuite/g++.dg/warn/Wparentheses-32.C
new file mode 100644
index 00000000000..719a9d9e73a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wparentheses-32.C
@@ -0,0 +1,28 @@
+// Verify we issue -Wparentheses warnings at template definition time
+// (for suitable non-dependent expressions).
+// { dg-additional-options "-Wparentheses" }
+
+struct X { operator bool(); };
+struct Y { Y& operator=(const Y&); operator bool(); };
+struct Z { int m; operator bool(); };
+
+template<class T>
+void f() {
+ int n, m;
+ if (n = m) { } // { dg-warning "parentheses" }
+
+ X x1, x2;
+ if (x1 = x2) { } // { dg-warning "parentheses" }
+
+ Y y1, y2;
+ if (y1 = y2) { } // { dg-warning "parentheses" }
+
+ Z z1, z2;
+ if (z1 = z2) { } // { dg-warning "parentheses" }
+
+ bool b;
+ b = m = n; // { dg-warning "parentheses" "" { xfail *-*-* } }
+ b = x1 = x2; // { dg-warning "parentheses" "" { xfail *-*-* } }
+ b = y1 = y2; // { dg-warning "parentheses" "" { xfail *-*-* } }
+ b = z1 = z2; // { dg-warning "parentheses" "" { xfail *-*-* } }
+}
diff --git a/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc
index 720ce96dc28..0d7e667382d 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc
index f378621805f..2ef563038cc 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
index c1cfe9da7fb..071ed75d8d8 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc
index 52476026533..2fb9622fda0 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc
index 1ca783e3044..3fa9c9ad8d3 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc
index 08beb3bcf93..25d19a0ba66 100644
--- a/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc
@@ -51,7 +51,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
diff --git a/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
index b629053585e..fe798f2f05b 100644
--- a/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
+++ b/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
@@ -52,7 +52,7 @@ struct seed_seq
// T is convertible to the engine's result_type:
operator T() const noexcept { return T(); }
- bool called = false;
+ mutable bool called = false;
};
using engine_type
--
2.42.0.216.gbda494f404
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] c++: non-dependent assignment checking [PR63198, PR18474]
2023-09-18 13:12 ` Patrick Palka
@ 2023-09-18 13:33 ` Jason Merrill
0 siblings, 0 replies; 4+ messages in thread
From: Jason Merrill @ 2023-09-18 13:33 UTC (permalink / raw)
To: Patrick Palka; +Cc: gcc-patches, libstdc++
On 9/18/23 09:12, Patrick Palka wrote:
> On Sun, 17 Sep 2023, Jason Merrill wrote:
>
>> On 9/17/23 14:51, Patrick Palka wrote:
>>> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
>>> trunk? Patch generatde with -w to avoid noisy whitespace changes.
>>>
>>> -- >8 --
>>>
>>> This patch makes us recognize and check non-dependent simple assigments
>>> ahead of time, like we already do for compound assignments. This means
>>> the templated representation of such assignments will now usually have
>>> an implicit INDIRECT_REF (due to the reference return type), which the
>>> -Wparentheses code needs to handle. As a drive-by improvement, this
>>> patch also makes maybe_convert_cond issue -Wparentheses warnings ahead
>>> of time.
>>>
>>> This revealed some libstdc++ tests were attempting to modify a data
>>> member from a uninstantiated const member function; naively fixed by
>>> making the data member mutable.
>>>
>>> PR c++/63198
>>> PR c++/18474
>>>
>>> gcc/cp/ChangeLog:
>>>
>>> * semantics.cc (maybe_convert_cond): Look through implicit
>>> INDIRECT_REF when deciding whether to issue a -Wparentheses
>>> warning, and consider templated assignment expressions as well.
>>> (finish_parenthesized_expr): Look through implicit INDIRECT_REF
>>> when suppressing -Wparentheses warning.
>>> * typeck.cc (build_x_modify_expr): Check simple assignments
>>> ahead time too, not just compound assignments. Give the second
>>> operand of MODOP_EXPR a non-null type so that it's not considered
>>> always instantiation-dependent.
>>>
>>> gcc/testsuite/ChangeLog:
>>>
>>> * g++.dg/cpp0x/static_assert15.C: Expect diagnostic for
>>> non-constant static_assert condition.
>>> * g++.dg/expr/unary2.C: Remove xfails.
>>> * g++.dg/template/init7.C: Make initializer type-dependent to
>>> preserve intent of test.
>>> * g++.dg/template/recurse3.C: Likewise for the erroneous
>>> statement.
>>> * g++.dg/template/non-dependent26.C: New test.
>>> * g++.dg/warn/Wparentheses-32.C: New test.
>>>
>>> libstdc++/ChangeLog:
>>>
>>> * testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc:
>>> Make seed_seq::called member mutable.
>>> *
>>> testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc:
>>> Likewise.
>>> *
>>> testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
>>> Likewise.
>>> *
>>> testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc:
>>> Likewise.
>>> * testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc:
>>> Likewise.
>>> *
>>> testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc:
>>> Likewise.
>>> *
>>> testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
>>> Likewise.
>>> ---
>>> gcc/cp/semantics.cc | 17 +++++++----
>>> gcc/cp/typeck.cc | 23 +++++++--------
>>> gcc/testsuite/g++.dg/cpp0x/static_assert15.C | 2 +-
>>> gcc/testsuite/g++.dg/expr/unary2.C | 8 ++----
>>> gcc/testsuite/g++.dg/template/init7.C | 2 +-
>>> .../g++.dg/template/non-dependent26.C | 25 +++++++++++++++++
>>> gcc/testsuite/g++.dg/template/recurse3.C | 8 +++---
>>> gcc/testsuite/g++.dg/warn/Wparentheses-32.C | 28 +++++++++++++++++++
>>> .../discard_block_engine/cons/seed_seq2.cc | 2 +-
>>> .../independent_bits_engine/cons/seed_seq2.cc | 2 +-
>>> .../cons/seed_seq2.cc | 2 +-
>>> .../mersenne_twister_engine/cons/seed_seq2.cc | 2 +-
>>> .../shuffle_order_engine/cons/seed_seq2.cc | 2 +-
>>> .../cons/seed_seq2.cc | 2 +-
>>> .../cons/seed_seq2.cc | 2 +-
>>> 15 files changed, 91 insertions(+), 36 deletions(-)
>>> create mode 100644 gcc/testsuite/g++.dg/template/non-dependent26.C
>>> create mode 100644 gcc/testsuite/g++.dg/warn/Wparentheses-32.C
>>>
>>> diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
>>> index 0f7f4e87ae4..b57c1ac868b 100644
>>> --- a/gcc/cp/semantics.cc
>>> +++ b/gcc/cp/semantics.cc
>>> diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
>>> index 459739d5866..74f5fced060 100644
>>> --- a/gcc/cp/typeck.cc
>>> +++ b/gcc/cp/typeck.cc
>>> @@ -9739,15 +9739,15 @@ build_x_modify_expr (location_t loc, tree lhs, enum
>>> tree_code modifycode,
>>> rhs = build_non_dependent_expr (rhs);
>>> }
>>> - if (modifycode != NOP_EXPR)
>>> - {
>>> - tree op = build_nt (modifycode, NULL_TREE, NULL_TREE);
>>> - tree rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
>>> + tree rval;
>>> + if (modifycode == NOP_EXPR)
>>> + rval = cp_build_modify_expr (loc, lhs, modifycode, rhs, complain);
>>> + else
>>> + rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
>>> lhs, rhs, op, lookups, &overload, complain);
>>> - if (rval)
>>> - {
>>> if (rval == error_mark_node)
>>> - return rval;
>>> + return error_mark_node;
>>> + if (modifycode != NOP_EXPR)
>>> suppress_warning (rval /* What warning? */);
>>
>> Did you try disabling this to see if it's still needed?
>
> Looks like it's not needed as far as bootstrap + regtest is concerned.
> FWIW this line originally was added in
> https://gcc.gnu.org/pipermail/gcc-patches/2004-July/144621.html
> to suppress -Wparentheses warnings for non-templated compound assignment
> operator expressions.
>
> Here's a patch that also gets rid of that suppress_warning call:
OK.
> -- >8 --
>
> Subject: [PATCH] c++: non-dependent assignment checking [PR63198, PR18474]
>
> PR c++/63198
> PR c++/18474
>
> gcc/cp/ChangeLog:
>
> * semantics.cc (maybe_convert_cond): Look through implicit
> INDIRECT_REF when deciding whether to issue a -Wparentheses
> warning, and consider templated assignment expressions as well.
> (finish_parenthesized_expr): Look through implicit INDIRECT_REF
> when suppressing -Wparentheses warning.
> * typeck.cc (build_x_modify_expr): Check simple assignments
> ahead time too, not just compound assignments. Give the second
> operand of MODOP_EXPR a non-null type so that it's not considered
> always instantiation-dependent. Don't call suppress_warning.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/cpp0x/static_assert15.C: Expect diagnostic for
> non-constant static_assert condition.
> * g++.dg/expr/unary2.C: Remove xfails.
> * g++.dg/template/init7.C: Make initializer type-dependent to
> preserve intent of test.
> * g++.dg/template/recurse3.C: Likewise for the erroneous
> statement.
> * g++.dg/template/non-dependent26.C: New test.
> * g++.dg/warn/Wparentheses-32.C: New test.
>
> libstdc++/ChangeLog:
>
> * testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc:
> Make data member seed_seq::called mutable.
> * testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc:
> Likewise.
> * testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
> Likewise.
> * testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc:
> Likewise.
> * testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc:
> Likewise.
> * testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc:
> Likewise.
> * testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
> Likewise.
> ---
> gcc/cp/semantics.cc | 19 ++++++---
> gcc/cp/typeck.cc | 41 ++++++++-----------
> gcc/testsuite/g++.dg/cpp0x/static_assert15.C | 2 +-
> gcc/testsuite/g++.dg/expr/unary2.C | 8 ++--
> gcc/testsuite/g++.dg/template/init7.C | 2 +-
> .../g++.dg/template/non-dependent26.C | 25 +++++++++++
> gcc/testsuite/g++.dg/template/recurse3.C | 8 ++--
> gcc/testsuite/g++.dg/warn/Wparentheses-32.C | 28 +++++++++++++
> .../discard_block_engine/cons/seed_seq2.cc | 2 +-
> .../independent_bits_engine/cons/seed_seq2.cc | 2 +-
> .../cons/seed_seq2.cc | 2 +-
> .../mersenne_twister_engine/cons/seed_seq2.cc | 2 +-
> .../shuffle_order_engine/cons/seed_seq2.cc | 2 +-
> .../cons/seed_seq2.cc | 2 +-
> .../cons/seed_seq2.cc | 2 +-
> 15 files changed, 100 insertions(+), 47 deletions(-)
> create mode 100644 gcc/testsuite/g++.dg/template/non-dependent26.C
> create mode 100644 gcc/testsuite/g++.dg/warn/Wparentheses-32.C
>
> diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
> index 0f7f4e87ae4..4109ac33654 100644
> --- a/gcc/cp/semantics.cc
> +++ b/gcc/cp/semantics.cc
> @@ -881,13 +881,17 @@ maybe_convert_cond (tree cond)
> /* Do the conversion. */
> cond = convert_from_reference (cond);
>
> - if ((TREE_CODE (cond) == MODIFY_EXPR || is_assignment_op_expr_p (cond))
> + tree inner = REFERENCE_REF_P (cond) ? TREE_OPERAND (cond, 0) : cond;
> + if ((TREE_CODE (inner) == MODIFY_EXPR
> + || (TREE_CODE (inner) == MODOP_EXPR
> + && TREE_CODE (TREE_OPERAND (inner, 1)) == NOP_EXPR)
> + || is_assignment_op_expr_p (inner))
> && warn_parentheses
> - && !warning_suppressed_p (cond, OPT_Wparentheses)
> - && warning_at (cp_expr_loc_or_input_loc (cond),
> + && !warning_suppressed_p (inner, OPT_Wparentheses)
> + && warning_at (cp_expr_loc_or_input_loc (inner),
> OPT_Wparentheses, "suggest parentheses around "
> "assignment used as truth value"))
> - suppress_warning (cond, OPT_Wparentheses);
> + suppress_warning (inner, OPT_Wparentheses);
>
> return condition_conversion (cond);
> }
> @@ -2155,8 +2159,11 @@ cp_expr
> finish_parenthesized_expr (cp_expr expr)
> {
> if (EXPR_P (expr))
> - /* This inhibits warnings in c_common_truthvalue_conversion. */
> - suppress_warning (expr, OPT_Wparentheses);
> + {
> + /* This inhibits warnings in c_common_truthvalue_conversion. */
> + tree inner = REFERENCE_REF_P (expr) ? TREE_OPERAND (expr, 0) : *expr;
> + suppress_warning (inner, OPT_Wparentheses);
> + }
>
> if (TREE_CODE (expr) == OFFSET_REF
> || TREE_CODE (expr) == SCOPE_REF)
> diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
> index 459739d5866..8132bd7fccc 100644
> --- a/gcc/cp/typeck.cc
> +++ b/gcc/cp/typeck.cc
> @@ -9721,13 +9721,13 @@ build_x_modify_expr (location_t loc, tree lhs, enum tree_code modifycode,
> if (lhs == error_mark_node || rhs == error_mark_node)
> return cp_expr (error_mark_node, loc);
>
> + tree op = build_min (modifycode, void_type_node, NULL_TREE, NULL_TREE);
> +
> if (processing_template_decl)
> {
> - if (modifycode == NOP_EXPR
> - || type_dependent_expression_p (lhs)
> + if (type_dependent_expression_p (lhs)
> || type_dependent_expression_p (rhs))
> {
> - tree op = build_min_nt_loc (loc, modifycode, NULL_TREE, NULL_TREE);
> tree rval = build_min_nt_loc (loc, MODOP_EXPR, lhs, op, rhs);
> if (modifycode != NOP_EXPR)
> TREE_TYPE (rval)
> @@ -9739,29 +9739,24 @@ build_x_modify_expr (location_t loc, tree lhs, enum tree_code modifycode,
> rhs = build_non_dependent_expr (rhs);
> }
>
> - if (modifycode != NOP_EXPR)
> + tree rval;
> + if (modifycode == NOP_EXPR)
> + rval = cp_build_modify_expr (loc, lhs, modifycode, rhs, complain);
> + else
> + rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
> + lhs, rhs, op, lookups, &overload, complain);
> + if (rval == error_mark_node)
> + return error_mark_node;
> + if (processing_template_decl)
> {
> - tree op = build_nt (modifycode, NULL_TREE, NULL_TREE);
> - tree rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL,
> - lhs, rhs, op, lookups, &overload, complain);
> - if (rval)
> - {
> - if (rval == error_mark_node)
> - return rval;
> - suppress_warning (rval /* What warning? */);
> - if (processing_template_decl)
> - {
> - if (overload != NULL_TREE)
> - return (build_min_non_dep_op_overload
> - (MODIFY_EXPR, rval, overload, orig_lhs, orig_rhs));
> + if (overload != NULL_TREE)
> + return (build_min_non_dep_op_overload
> + (MODIFY_EXPR, rval, overload, orig_lhs, orig_rhs));
>
> - return (build_min_non_dep
> - (MODOP_EXPR, rval, orig_lhs, op, orig_rhs));
> - }
> - return rval;
> - }
> + return (build_min_non_dep
> + (MODOP_EXPR, rval, orig_lhs, op, orig_rhs));
> }
> - return cp_build_modify_expr (loc, lhs, modifycode, rhs, complain);
> + return rval;
> }
>
> /* Helper function for get_delta_difference which assumes FROM is a base
> diff --git a/gcc/testsuite/g++.dg/cpp0x/static_assert15.C b/gcc/testsuite/g++.dg/cpp0x/static_assert15.C
> index a740f73fd4a..d5f50d07c91 100644
> --- a/gcc/testsuite/g++.dg/cpp0x/static_assert15.C
> +++ b/gcc/testsuite/g++.dg/cpp0x/static_assert15.C
> @@ -5,6 +5,6 @@ template<int x>
> struct a {
> constexpr void b() {
> int c;
> - static_assert(c %= 1, "");
> + static_assert(c %= 1, ""); // { dg-error "constant" }
> }
> };
> diff --git a/gcc/testsuite/g++.dg/expr/unary2.C b/gcc/testsuite/g++.dg/expr/unary2.C
> index 5962bfe19c9..4db68375944 100644
> --- a/gcc/testsuite/g++.dg/expr/unary2.C
> +++ b/gcc/testsuite/g++.dg/expr/unary2.C
> @@ -1,9 +1,7 @@
> +// PR c++/18474
> // { dg-do compile }
> // Unary plus/minus are not lvalues.
>
> -// In templates we require an instantiation to emit the diagnostic. This
> -// is wrong and it is PR 18474.
> -
> int n;
>
> void f(void)
> @@ -15,6 +13,6 @@ void f(void)
> template <int>
> void g(void)
> {
> - -n = 0; // { dg-error "lvalue" "" { xfail *-*-* } }
> - +n = 0; // { dg-error "lvalue" "" { xfail *-*-* } }
> + -n = 0; // { dg-error "lvalue" "" }
> + +n = 0; // { dg-error "lvalue" "" }
> }
> diff --git a/gcc/testsuite/g++.dg/template/init7.C b/gcc/testsuite/g++.dg/template/init7.C
> index bb26c8f92b5..94fc22f578c 100644
> --- a/gcc/testsuite/g++.dg/template/init7.C
> +++ b/gcc/testsuite/g++.dg/template/init7.C
> @@ -6,4 +6,4 @@ template<typename> struct A
> static const int i=0;
> };
>
> -template<typename T> const int A<T>::i = 0=0; /* { dg-error "duplicate initialization" } */
> +template<typename T> const int A<T>::i = T()=0; /* { dg-error "duplicate initialization" } */
> diff --git a/gcc/testsuite/g++.dg/template/non-dependent26.C b/gcc/testsuite/g++.dg/template/non-dependent26.C
> new file mode 100644
> index 00000000000..1faa39a4b1a
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/template/non-dependent26.C
> @@ -0,0 +1,25 @@
> +// Verify non-dependent assignment expressions are recognized as such
> +// and are checked ahead of time.
> +// PR c++/63198
> +// { dg-do compile { target c++11 } }
> +
> +struct X { using t1 = int; };
> +struct Y { X operator=(const Y&); } y;
> +template<class T> void f1(decltype(y = y)::t1);
> +
> +int n;
> +template<class T> void f2(decltype(n = n)::t1); // { dg-error "not a class" }
> +template<class T> void f3(decltype(n += n)::t1); // { dg-error "not a class" }
> +
> +template<class T>
> +void g() {
> + const int n;
> + n = 42; // { dg-error "read-only" }
> +
> + const X x;
> + x = {}; // { dg-error "no match" }
> +
> + const Y y;
> + y = {}; // { dg-error "no match" }
> + Y{} = X{}; // { dg-error "no match" }
> +}
> diff --git a/gcc/testsuite/g++.dg/template/recurse3.C b/gcc/testsuite/g++.dg/template/recurse3.C
> index f1db7c5cbca..70c6152d063 100644
> --- a/gcc/testsuite/g++.dg/template/recurse3.C
> +++ b/gcc/testsuite/g++.dg/template/recurse3.C
> @@ -1,14 +1,14 @@
> // PR c++/44609
> // { dg-options -ftemplate-depth=10 }
>
> -template<int N>
> +template<class T, int N>
> void f()
> {
> - 0 = 0; // { dg-error "lvalue required" }
> - f<N+1>(); // { dg-bogus "instantiation depth" }
> + T(0) = 0; // { dg-error "lvalue required" }
> + f<T, N+1>(); // { dg-bogus "instantiation depth" }
> }
>
> int main()
> {
> - f<0>();
> + f<int, 0>();
> }
> diff --git a/gcc/testsuite/g++.dg/warn/Wparentheses-32.C b/gcc/testsuite/g++.dg/warn/Wparentheses-32.C
> new file mode 100644
> index 00000000000..719a9d9e73a
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/warn/Wparentheses-32.C
> @@ -0,0 +1,28 @@
> +// Verify we issue -Wparentheses warnings at template definition time
> +// (for suitable non-dependent expressions).
> +// { dg-additional-options "-Wparentheses" }
> +
> +struct X { operator bool(); };
> +struct Y { Y& operator=(const Y&); operator bool(); };
> +struct Z { int m; operator bool(); };
> +
> +template<class T>
> +void f() {
> + int n, m;
> + if (n = m) { } // { dg-warning "parentheses" }
> +
> + X x1, x2;
> + if (x1 = x2) { } // { dg-warning "parentheses" }
> +
> + Y y1, y2;
> + if (y1 = y2) { } // { dg-warning "parentheses" }
> +
> + Z z1, z2;
> + if (z1 = z2) { } // { dg-warning "parentheses" }
> +
> + bool b;
> + b = m = n; // { dg-warning "parentheses" "" { xfail *-*-* } }
> + b = x1 = x2; // { dg-warning "parentheses" "" { xfail *-*-* } }
> + b = y1 = y2; // { dg-warning "parentheses" "" { xfail *-*-* } }
> + b = z1 = z2; // { dg-warning "parentheses" "" { xfail *-*-* } }
> +}
> diff --git a/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc
> index 720ce96dc28..0d7e667382d 100644
> --- a/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc
> +++ b/libstdc++-v3/testsuite/26_numerics/random/discard_block_engine/cons/seed_seq2.cc
> @@ -51,7 +51,7 @@ struct seed_seq
> // T is convertible to the engine's result_type:
> operator T() const noexcept { return T(); }
>
> - bool called = false;
> + mutable bool called = false;
> };
>
> using engine_type
> diff --git a/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc
> index f378621805f..2ef563038cc 100644
> --- a/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc
> +++ b/libstdc++-v3/testsuite/26_numerics/random/independent_bits_engine/cons/seed_seq2.cc
> @@ -51,7 +51,7 @@ struct seed_seq
> // T is convertible to the engine's result_type:
> operator T() const noexcept { return T(); }
>
> - bool called = false;
> + mutable bool called = false;
> };
>
> using engine_type
> diff --git a/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
> index c1cfe9da7fb..071ed75d8d8 100644
> --- a/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
> +++ b/libstdc++-v3/testsuite/26_numerics/random/linear_congruential_engine/cons/seed_seq2.cc
> @@ -51,7 +51,7 @@ struct seed_seq
> // T is convertible to the engine's result_type:
> operator T() const noexcept { return T(); }
>
> - bool called = false;
> + mutable bool called = false;
> };
>
> using engine_type
> diff --git a/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc
> index 52476026533..2fb9622fda0 100644
> --- a/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc
> +++ b/libstdc++-v3/testsuite/26_numerics/random/mersenne_twister_engine/cons/seed_seq2.cc
> @@ -51,7 +51,7 @@ struct seed_seq
> // T is convertible to the engine's result_type:
> operator T() const noexcept { return T(); }
>
> - bool called = false;
> + mutable bool called = false;
> };
>
> using engine_type
> diff --git a/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc
> index 1ca783e3044..3fa9c9ad8d3 100644
> --- a/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc
> +++ b/libstdc++-v3/testsuite/26_numerics/random/shuffle_order_engine/cons/seed_seq2.cc
> @@ -51,7 +51,7 @@ struct seed_seq
> // T is convertible to the engine's result_type:
> operator T() const noexcept { return T(); }
>
> - bool called = false;
> + mutable bool called = false;
> };
>
> using engine_type
> diff --git a/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc
> index 08beb3bcf93..25d19a0ba66 100644
> --- a/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc
> +++ b/libstdc++-v3/testsuite/26_numerics/random/subtract_with_carry_engine/cons/seed_seq2.cc
> @@ -51,7 +51,7 @@ struct seed_seq
> // T is convertible to the engine's result_type:
> operator T() const noexcept { return T(); }
>
> - bool called = false;
> + mutable bool called = false;
> };
>
> using engine_type
> diff --git a/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc b/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
> index b629053585e..fe798f2f05b 100644
> --- a/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
> +++ b/libstdc++-v3/testsuite/ext/random/simd_fast_mersenne_twister_engine/cons/seed_seq2.cc
> @@ -52,7 +52,7 @@ struct seed_seq
> // T is convertible to the engine's result_type:
> operator T() const noexcept { return T(); }
>
> - bool called = false;
> + mutable bool called = false;
> };
>
> using engine_type
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2023-09-18 13:33 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2023-09-17 18:51 [PATCH] c++: non-dependent assignment checking [PR63198, PR18474] Patrick Palka
2023-09-18 3:01 ` Jason Merrill
2023-09-18 13:12 ` Patrick Palka
2023-09-18 13:33 ` Jason Merrill
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