[PATCH 1/2] Fix ICE due to c_safe_arg_type_equiv_p not checking for error_mark node

[PATCH 1/2] Fix ICE due to c_safe_arg_type_equiv_p not checking for error_mark node

[Andrew Pinski]

This is a simple error recovery issue when c_safe_arg_type_equiv_p
was added in r8-5312-gc65e18d3331aa999. The issue is that after
an error, an argument type (of a function type) might turn
into an error mark node and c_safe_arg_type_equiv_p was not ready
for that. So this just adds a check for error operand for its
arguments before getting the main variant.

OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

	PR c/101285

gcc/c/ChangeLog:

	* c-typeck.cc (c_safe_arg_type_equiv_p): Return true for error
	operands early.

gcc/testsuite/ChangeLog:

	* gcc.dg/pr101285-1.c: New test.
---
 gcc/c/c-typeck.cc                 |  3 +++
 gcc/testsuite/gcc.dg/pr101285-1.c | 10 ++++++++++
 2 files changed, 13 insertions(+)
 create mode 100644 gcc/testsuite/gcc.dg/pr101285-1.c

diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc
index e55e887da14..6e044b4afbc 100644
--- a/gcc/c/c-typeck.cc
+++ b/gcc/c/c-typeck.cc
@@ -5960,6 +5960,9 @@ handle_warn_cast_qual (location_t loc, tree type, tree otype)
 static bool
 c_safe_arg_type_equiv_p (tree t1, tree t2)
 {
+  if (error_operand_p (t1) || error_operand_p (t2))
+    return true;
+
   t1 = TYPE_MAIN_VARIANT (t1);
   t2 = TYPE_MAIN_VARIANT (t2);
 
diff --git a/gcc/testsuite/gcc.dg/pr101285-1.c b/gcc/testsuite/gcc.dg/pr101285-1.c
new file mode 100644
index 00000000000..831e35f7662
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr101285-1.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-W -Wall" } */
+const int b;
+typedef void (*ft1)(int[b++]); /* { dg-error "read-only variable" } */
+void bar(int * z);
+void baz()
+{
+    (ft1) bar; /* { dg-warning "statement with no effect" } */
+}
+
-- 
2.39.3

[PATCH 2/2] [c] Fix PR 101364: ICE after error due to diagnose_arglist_conflict not checking for error

[Andrew Pinski]

When checking to see if we have a function declaration has a conflict due to
promotations, there is no test to see if the type was an error mark and then calls
c_type_promotes_to. c_type_promotes_to is not ready for error_mark and causes an
ICE.

This adds a check for error before the call of c_type_promotes_to.

OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

	PR c/101364

gcc/c/ChangeLog:

	* c-decl.cc (diagnose_arglist_conflict): Test for
	error mark before calling of c_type_promotes_to.

gcc/testsuite/ChangeLog:

	* gcc.dg/pr101364-1.c: New test.
---
 gcc/c/c-decl.cc                   | 3 ++-
 gcc/testsuite/gcc.dg/pr101364-1.c | 8 ++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/gcc.dg/pr101364-1.c

diff --git a/gcc/c/c-decl.cc b/gcc/c/c-decl.cc
index 5822faf01b4..eb2df08c0a7 100644
--- a/gcc/c/c-decl.cc
+++ b/gcc/c/c-decl.cc
@@ -1899,7 +1899,8 @@ diagnose_arglist_conflict (tree newdecl, tree olddecl,
 	  break;
 	}
 
-      if (c_type_promotes_to (type) != type)
+      if (!error_operand_p (type)
+	  && c_type_promotes_to (type) != type)
 	{
 	  inform (input_location, "an argument type that has a default "
 		  "promotion cannot match an empty parameter name list "
diff --git a/gcc/testsuite/gcc.dg/pr101364-1.c b/gcc/testsuite/gcc.dg/pr101364-1.c
new file mode 100644
index 00000000000..e7c94a05553
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr101364-1.c
@@ -0,0 +1,8 @@
+/* { dg-do compile } */
+/* { dg-options "-std=c90 "} */
+
+void fruit(); /* { dg-message "previous declaration" } */
+void fruit( /* { dg-error "conflicting types for" } */
+    int b[x], /* { dg-error "undeclared " } */
+    short c)
+{} /* { dg-message "an argument type that has a" } */
-- 
2.39.3

Re: [PATCH 2/2] [c] Fix PR 101364: ICE after error due to diagnose_arglist_conflict not checking for error

[Joseph Myers]

On Sat, 14 Oct 2023, Andrew Pinski wrote:

> When checking to see if we have a function declaration has a conflict due to
> promotations, there is no test to see if the type was an error mark and then calls
> c_type_promotes_to. c_type_promotes_to is not ready for error_mark and causes an
> ICE.
> 
> This adds a check for error before the call of c_type_promotes_to.
> 
> OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

OK.

-- 
Joseph S. Myers
joseph@codesourcery.com

Re: [PATCH 1/2] Fix ICE due to c_safe_arg_type_equiv_p not checking for error_mark node

[Joseph Myers]

On Sat, 14 Oct 2023, Andrew Pinski wrote:

> This is a simple error recovery issue when c_safe_arg_type_equiv_p
> was added in r8-5312-gc65e18d3331aa999. The issue is that after
> an error, an argument type (of a function type) might turn
> into an error mark node and c_safe_arg_type_equiv_p was not ready
> for that. So this just adds a check for error operand for its
> arguments before getting the main variant.
> 
> OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

OK.

-- 
Joseph S. Myers
joseph@codesourcery.com

Re: [PATCH 1/2] Fix ICE due to c_safe_arg_type_equiv_p not checking for error_mark node

[Marek Polacek]

On Sat, Oct 14, 2023 at 06:16:47PM -0700, Andrew Pinski wrote:
> This is a simple error recovery issue when c_safe_arg_type_equiv_p
> was added in r8-5312-gc65e18d3331aa999. The issue is that after
> an error, an argument type (of a function type) might turn
> into an error mark node and c_safe_arg_type_equiv_p was not ready
> for that. So this just adds a check for error operand for its
> arguments before getting the main variant.
> 
> OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

Please don't include this line in the commit message.
 
> 	PR c/101285
> 
> gcc/c/ChangeLog:
> 
> 	* c-typeck.cc (c_safe_arg_type_equiv_p): Return true for error
> 	operands early.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* gcc.dg/pr101285-1.c: New test.
> ---
>  gcc/c/c-typeck.cc                 |  3 +++
>  gcc/testsuite/gcc.dg/pr101285-1.c | 10 ++++++++++
>  2 files changed, 13 insertions(+)
>  create mode 100644 gcc/testsuite/gcc.dg/pr101285-1.c
> 
> diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc
> index e55e887da14..6e044b4afbc 100644
> --- a/gcc/c/c-typeck.cc
> +++ b/gcc/c/c-typeck.cc
> @@ -5960,6 +5960,9 @@ handle_warn_cast_qual (location_t loc, tree type, tree otype)
>  static bool
>  c_safe_arg_type_equiv_p (tree t1, tree t2)
>  {
> +  if (error_operand_p (t1) || error_operand_p (t2))
> +    return true;

I thought it would be more natural to return false but that would result in:
cast between incompatible function types from 'void (*)(int *)' to 'void (*)(<type-error>)'
but we don't want that so pretending the cast is safe is probably better.

>    t1 = TYPE_MAIN_VARIANT (t1);
>    t2 = TYPE_MAIN_VARIANT (t2);
>  
> diff --git a/gcc/testsuite/gcc.dg/pr101285-1.c b/gcc/testsuite/gcc.dg/pr101285-1.c
> new file mode 100644
> index 00000000000..831e35f7662
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/pr101285-1.c
> @@ -0,0 +1,10 @@

Let's put

/* PR c/101285 */

here.

> +/* { dg-do compile } */
> +/* { dg-options "-W -Wall" } */
> +const int b;
> +typedef void (*ft1)(int[b++]); /* { dg-error "read-only variable" } */
> +void bar(int * z);
> +void baz()
> +{
> +    (ft1) bar; /* { dg-warning "statement with no effect" } */
> +}
> +

Extra newline.

Thanks,
Marek