diff options
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr71452.c | 10 | ||||
| -rw-r--r-- | gcc/tree-ssa.c | 8 |
4 files changed, 30 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 6ad6ddc..4f5d317 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2016-06-08 Richard Biener <rguenther@suse.de> + + PR tree-optimization/71452 + * tree-ssa.c (non_rewritable_lvalue_p): Make sure that the + type used for the SSA rewrite has enough precision to cover + the dynamic type of the location. + 2016-06-08 Jakub Jelinek <jakub@redhat.com> Richard Biener <rguenther@suse.de> diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index d8b668c..28b17cf 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2016-06-08 Richard Biener <rguenther@suse.de> + + PR tree-optimization/71452 + * gcc.dg/torture/pr71452.c: New testcase. + 2016-06-08 Jakub Jelinek <jakub@redhat.com> PR c++/71448 diff --git a/gcc/testsuite/gcc.dg/torture/pr71452.c b/gcc/testsuite/gcc.dg/torture/pr71452.c new file mode 100644 index 0000000..8948d39 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr71452.c @@ -0,0 +1,10 @@ +/* { dg-do run } */ + +int main() +{ + _Bool b; + *(char *)&b = 123; + if (*(char *)&b != 123) + __builtin_abort (); + return 0; +} diff --git a/gcc/tree-ssa.c b/gcc/tree-ssa.c index 2f3caf3..30c6269 100644 --- a/gcc/tree-ssa.c +++ b/gcc/tree-ssa.c @@ -1292,6 +1292,14 @@ non_rewritable_lvalue_p (tree lhs) if (integer_zerop (TREE_OPERAND (lhs, 1)) && DECL_P (decl) && DECL_SIZE (decl) == TYPE_SIZE (TREE_TYPE (lhs)) + /* If the dynamic type of the decl has larger precision than + the decl itself we can't use the decls type for SSA rewriting. */ + && ((! INTEGRAL_TYPE_P (TREE_TYPE (decl)) + || compare_tree_int (DECL_SIZE (decl), + TYPE_PRECISION (TREE_TYPE (decl))) == 0) + || (INTEGRAL_TYPE_P (TREE_TYPE (lhs)) + && (TYPE_PRECISION (TREE_TYPE (decl)) + >= TYPE_PRECISION (TREE_TYPE (lhs))))) && (TREE_THIS_VOLATILE (decl) == TREE_THIS_VOLATILE (lhs))) return false; |