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| author | Jakub Jelinek <jakub@redhat.com> | 2017-03-22 19:45:48 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2017-03-22 19:45:48 +0100 |
| commit | 68ed2ba0a7d60275ac044a4cb50b33eb33fbb813 (patch) | |
| tree | 1e4f17b8856d8dc6d804ba411cf9c40568e61ca9 /gcc | |
| parent | 0e2468e0ca0ad2e7adc0098f6a4061be7475fdc1 (diff) | |
| download | gcc-68ed2ba0a7d60275ac044a4cb50b33eb33fbb813.zip gcc-68ed2ba0a7d60275ac044a4cb50b33eb33fbb813.tar.gz gcc-68ed2ba0a7d60275ac044a4cb50b33eb33fbb813.tar.bz2 | |
re PR c++/80129 (wrong code with ternary struct assignment to const)
PR c++/80129
* gimplify.c (gimplify_modify_expr_rhs) <case COND_EXPR>: Clear
TREE_READONLY on result if writing it more than once.
* g++.dg/torture/pr80129.C: New test.
From-SVN: r246401
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/gimplify.c | 8 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 3 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/torture/pr80129.C | 14 |
4 files changed, 29 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index a1e007f..5259dce 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,9 @@ 2017-03-22 Jakub Jelinek <jakub@redhat.com> + PR c++/80129 + * gimplify.c (gimplify_modify_expr_rhs) <case COND_EXPR>: Clear + TREE_READONLY on result if writing it more than once. + PR sanitizer/80110 * doc/invoke.texi (-fsanitize=thread): Document that with -fnon-call-exceptions atomics are not able to throw diff --git a/gcc/gimplify.c b/gcc/gimplify.c index 5658d0a..f90ae94 100644 --- a/gcc/gimplify.c +++ b/gcc/gimplify.c @@ -5098,6 +5098,14 @@ gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, if (ret != GS_ERROR) ret = GS_OK; + /* If we are going to write RESULT more than once, clear + TREE_READONLY flag, otherwise we might incorrectly promote + the variable to static const and initialize it at compile + time in one of the branches. */ + if (VAR_P (result) + && TREE_TYPE (TREE_OPERAND (cond, 1)) != void_type_node + && TREE_TYPE (TREE_OPERAND (cond, 2)) != void_type_node) + TREE_READONLY (result) = 0; if (TREE_TYPE (TREE_OPERAND (cond, 1)) != void_type_node) TREE_OPERAND (cond, 1) = build2 (code, void_type_node, result, diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index d8b45dc..add3a14 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,5 +1,8 @@ 2017-03-22 Jakub Jelinek <jakub@redhat.com> + PR c++/80129 + * g++.dg/torture/pr80129.C: New test. + PR sanitizer/80110 * g++.dg/tsan/pr80110.C: New test. diff --git a/gcc/testsuite/g++.dg/torture/pr80129.C b/gcc/testsuite/g++.dg/torture/pr80129.C new file mode 100644 index 0000000..134293c --- /dev/null +++ b/gcc/testsuite/g++.dg/torture/pr80129.C @@ -0,0 +1,14 @@ +// PR c++/80129 +// { dg-do run } +// { dg-options "-std=c++11" } + +struct A { bool a; int b; }; + +int +main () +{ + bool c = false; + const A x = c ? A {true, 1} : A {false, 0}; + if (x.a) + __builtin_abort (); +} |