From: Jason Merrill <jason@redhat.com>
To: gcc-patches List <gcc-patches@gcc.gnu.org>
Subject: C++ PATCH for c++/34772 (warning about self-initialization without -Winit-self)
Date: Mon, 09 May 2011 18:37:00 -0000 [thread overview]
Message-ID: <4DC824D2.2060203@redhat.com> (raw)
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In this testcase -Wuninitialized was warning about 'int i = i' without
-Winit-self because the C++ front end always uses separate code for
non-constant initialization. But for simple initialization, it makes
sense to use DECL_INITIAL.
Tested x86_64-pc-linux-gnu, applying to trunk.
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[-- Type: text/plain, Size: 9179 bytes --]
commit b105bfbee01e9183e7fc100f3a33c7c109db7fae
Author: Jason Merrill <jason@redhat.com>
Date: Sat May 7 17:31:09 2011 -0400
PR c++/34772
* decl.c (initialize_local_var): Use DECL_INITIAL for simple
initialization.
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index c139f3f..c255e16 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -5689,21 +5689,32 @@ initialize_local_var (tree decl, tree init)
/* Perform the initialization. */
if (init)
{
- int saved_stmts_are_full_exprs_p;
+ if (TREE_CODE (init) == INIT_EXPR
+ && !TREE_SIDE_EFFECTS (TREE_OPERAND (init, 1)))
+ {
+ /* Stick simple initializers in DECL_INITIAL so that
+ -Wno-init-self works (c++/34772). */
+ gcc_assert (TREE_OPERAND (init, 0) == decl);
+ DECL_INITIAL (decl) = TREE_OPERAND (init, 1);
+ }
+ else
+ {
+ int saved_stmts_are_full_exprs_p;
- /* If we're only initializing a single object, guard the destructors
- of any temporaries used in its initializer with its destructor.
- This isn't right for arrays because each element initialization is
- a full-expression. */
- if (cleanup && TREE_CODE (type) != ARRAY_TYPE)
- wrap_temporary_cleanups (init, cleanup);
+ /* If we're only initializing a single object, guard the
+ destructors of any temporaries used in its initializer with
+ its destructor. This isn't right for arrays because each
+ element initialization is a full-expression. */
+ if (cleanup && TREE_CODE (type) != ARRAY_TYPE)
+ wrap_temporary_cleanups (init, cleanup);
- gcc_assert (building_stmt_tree ());
- saved_stmts_are_full_exprs_p = stmts_are_full_exprs_p ();
- current_stmt_tree ()->stmts_are_full_exprs_p = 1;
- finish_expr_stmt (init);
- current_stmt_tree ()->stmts_are_full_exprs_p =
- saved_stmts_are_full_exprs_p;
+ gcc_assert (building_stmt_tree ());
+ saved_stmts_are_full_exprs_p = stmts_are_full_exprs_p ();
+ current_stmt_tree ()->stmts_are_full_exprs_p = 1;
+ finish_expr_stmt (init);
+ current_stmt_tree ()->stmts_are_full_exprs_p =
+ saved_stmts_are_full_exprs_p;
+ }
}
/* Set this to 0 so we can tell whether an aggregate which was
diff --git a/gcc/testsuite/c-c++-common/uninit-D-O0.c b/gcc/testsuite/c-c++-common/uninit-D-O0.c
new file mode 100644
index 0000000..e63cb80
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/uninit-D-O0.c
@@ -0,0 +1,9 @@
+/* Test we do not warn about initializing variable with self. */
+/* { dg-do compile } */
+/* { dg-options "-Wuninitialized" } */
+
+int f()
+{
+ int i = i;
+ return i;
+}
diff --git a/gcc/testsuite/c-c++-common/uninit-D.c b/gcc/testsuite/c-c++-common/uninit-D.c
new file mode 100644
index 0000000..ea957e4
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/uninit-D.c
@@ -0,0 +1,9 @@
+/* Test we do not warn about initializing variable with self. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized" } */
+
+int f()
+{
+ int i = i;
+ return i;
+}
diff --git a/gcc/testsuite/c-c++-common/uninit-E-O0.c b/gcc/testsuite/c-c++-common/uninit-E-O0.c
new file mode 100644
index 0000000..2cc2459
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/uninit-E-O0.c
@@ -0,0 +1,9 @@
+/* Test we do warn about initializing variable with self when -Winit-self is supplied. */
+/* { dg-do compile } */
+/* { dg-options "-Wuninitialized -Winit-self" } */
+
+int f()
+{
+ int i = i; /* { dg-warning "i" "uninitialized variable warning" } */
+ return i;
+}
diff --git a/gcc/testsuite/c-c++-common/uninit-E.c b/gcc/testsuite/c-c++-common/uninit-E.c
new file mode 100644
index 0000000..eb356c3
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/uninit-E.c
@@ -0,0 +1,9 @@
+/* Test we do warn about initializing variable with self when -Winit-self is supplied. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized -Winit-self" } */
+
+int f()
+{
+ int i = i; /* { dg-warning "i" "uninitialized variable warning" } */
+ return i;
+}
diff --git a/gcc/testsuite/c-c++-common/uninit-F-O0.c b/gcc/testsuite/c-c++-common/uninit-F-O0.c
new file mode 100644
index 0000000..737cc65
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/uninit-F-O0.c
@@ -0,0 +1,9 @@
+/* Test we do warn about initializing variable with self in the initialization. */
+/* { dg-do compile } */
+/* { dg-options "-Wuninitialized" } */
+
+int f()
+{
+ int i = i + 1; /* { dg-warning "i" "uninitialized variable warning" } */
+ return i;
+}
diff --git a/gcc/testsuite/c-c++-common/uninit-F.c b/gcc/testsuite/c-c++-common/uninit-F.c
new file mode 100644
index 0000000..1dbb365
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/uninit-F.c
@@ -0,0 +1,9 @@
+/* Test we do warn about initializing variable with self in the initialization. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized" } */
+
+int f()
+{
+ int i = i + 1; /* { dg-warning "i" "uninitialized variable warning" } */
+ return i;
+}
diff --git a/gcc/testsuite/c-c++-common/uninit-G-O0.c b/gcc/testsuite/c-c++-common/uninit-G-O0.c
new file mode 100644
index 0000000..d6edffe
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/uninit-G-O0.c
@@ -0,0 +1,9 @@
+/* Test we do not warn about initializing variable with address of self in the initialization. */
+/* { dg-do compile } */
+/* { dg-options "-Wuninitialized" } */
+
+void *f()
+{
+ void *i = &i;
+ return i;
+}
diff --git a/gcc/testsuite/c-c++-common/uninit-G.c b/gcc/testsuite/c-c++-common/uninit-G.c
new file mode 100644
index 0000000..08f5f53
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/uninit-G.c
@@ -0,0 +1,9 @@
+/* Test we do not warn about initializing variable with address of self in the initialization. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized" } */
+
+void *f()
+{
+ void *i = &i;
+ return i;
+}
diff --git a/gcc/testsuite/gcc.dg/uninit-D-O0.c b/gcc/testsuite/gcc.dg/uninit-D-O0.c
deleted file mode 100644
index e63cb80..0000000
--- a/gcc/testsuite/gcc.dg/uninit-D-O0.c
+++ /dev/null
@@ -1,9 +0,0 @@
-/* Test we do not warn about initializing variable with self. */
-/* { dg-do compile } */
-/* { dg-options "-Wuninitialized" } */
-
-int f()
-{
- int i = i;
- return i;
-}
diff --git a/gcc/testsuite/gcc.dg/uninit-D.c b/gcc/testsuite/gcc.dg/uninit-D.c
deleted file mode 100644
index ea957e4..0000000
--- a/gcc/testsuite/gcc.dg/uninit-D.c
+++ /dev/null
@@ -1,9 +0,0 @@
-/* Test we do not warn about initializing variable with self. */
-/* { dg-do compile } */
-/* { dg-options "-O -Wuninitialized" } */
-
-int f()
-{
- int i = i;
- return i;
-}
diff --git a/gcc/testsuite/gcc.dg/uninit-E-O0.c b/gcc/testsuite/gcc.dg/uninit-E-O0.c
deleted file mode 100644
index 2cc2459..0000000
--- a/gcc/testsuite/gcc.dg/uninit-E-O0.c
+++ /dev/null
@@ -1,9 +0,0 @@
-/* Test we do warn about initializing variable with self when -Winit-self is supplied. */
-/* { dg-do compile } */
-/* { dg-options "-Wuninitialized -Winit-self" } */
-
-int f()
-{
- int i = i; /* { dg-warning "i" "uninitialized variable warning" } */
- return i;
-}
diff --git a/gcc/testsuite/gcc.dg/uninit-E.c b/gcc/testsuite/gcc.dg/uninit-E.c
deleted file mode 100644
index eb356c3..0000000
--- a/gcc/testsuite/gcc.dg/uninit-E.c
+++ /dev/null
@@ -1,9 +0,0 @@
-/* Test we do warn about initializing variable with self when -Winit-self is supplied. */
-/* { dg-do compile } */
-/* { dg-options "-O -Wuninitialized -Winit-self" } */
-
-int f()
-{
- int i = i; /* { dg-warning "i" "uninitialized variable warning" } */
- return i;
-}
diff --git a/gcc/testsuite/gcc.dg/uninit-F-O0.c b/gcc/testsuite/gcc.dg/uninit-F-O0.c
deleted file mode 100644
index 737cc65..0000000
--- a/gcc/testsuite/gcc.dg/uninit-F-O0.c
+++ /dev/null
@@ -1,9 +0,0 @@
-/* Test we do warn about initializing variable with self in the initialization. */
-/* { dg-do compile } */
-/* { dg-options "-Wuninitialized" } */
-
-int f()
-{
- int i = i + 1; /* { dg-warning "i" "uninitialized variable warning" } */
- return i;
-}
diff --git a/gcc/testsuite/gcc.dg/uninit-F.c b/gcc/testsuite/gcc.dg/uninit-F.c
deleted file mode 100644
index 1dbb365..0000000
--- a/gcc/testsuite/gcc.dg/uninit-F.c
+++ /dev/null
@@ -1,9 +0,0 @@
-/* Test we do warn about initializing variable with self in the initialization. */
-/* { dg-do compile } */
-/* { dg-options "-O -Wuninitialized" } */
-
-int f()
-{
- int i = i + 1; /* { dg-warning "i" "uninitialized variable warning" } */
- return i;
-}
diff --git a/gcc/testsuite/gcc.dg/uninit-G-O0.c b/gcc/testsuite/gcc.dg/uninit-G-O0.c
deleted file mode 100644
index d6edffe..0000000
--- a/gcc/testsuite/gcc.dg/uninit-G-O0.c
+++ /dev/null
@@ -1,9 +0,0 @@
-/* Test we do not warn about initializing variable with address of self in the initialization. */
-/* { dg-do compile } */
-/* { dg-options "-Wuninitialized" } */
-
-void *f()
-{
- void *i = &i;
- return i;
-}
diff --git a/gcc/testsuite/gcc.dg/uninit-G.c b/gcc/testsuite/gcc.dg/uninit-G.c
deleted file mode 100644
index 08f5f53..0000000
--- a/gcc/testsuite/gcc.dg/uninit-G.c
+++ /dev/null
@@ -1,9 +0,0 @@
-/* Test we do not warn about initializing variable with address of self in the initialization. */
-/* { dg-do compile } */
-/* { dg-options "-O -Wuninitialized" } */
-
-void *f()
-{
- void *i = &i;
- return i;
-}
next reply other threads:[~2011-05-09 17:31 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-09 18:37 Jason Merrill [this message]
2011-05-21 22:07 ` H.J. Lu
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