diff options
| author | Martin Uecker <muecker@gwdg.de> | 2021-08-10 07:42:51 +0200 |
|---|---|---|
| committer | Martin Uecker <muecker@gwdg.de> | 2021-08-10 07:49:57 +0200 |
| commit | 0631faf87a197145acd833249bf8f20a1c4aaabf (patch) | |
| tree | 0ec94e5d7ad338e9051b5b6560b5521597d01687 | |
| parent | 3d7ccbc1efbd475031a9a4a6110c531f71fbf631 (diff) | |
| download | gcc-0631faf87a197145acd833249bf8f20a1c4aaabf.zip gcc-0631faf87a197145acd833249bf8f20a1c4aaabf.tar.gz gcc-0631faf87a197145acd833249bf8f20a1c4aaabf.tar.bz2 | |
Evaluate arguments of sizeof that are structs of variable size.
Evaluate arguments of sizeof for all types of variable size
and not just for VLAs. This fixes some issues related to
[PR29970] where statement expressions need to be evaluated
so that the size is well defined.
2021-08-10 Martin Uecker <muecker@gwdg.de>
gcc/c/
PR c/29970
* c-typeck.c (c_expr_sizeof_expr): Evaluate
size expressions for structs of variable size.
gcc/testsuite/
PR c/29970
* gcc.dg/vla-stexp-1.c: New test.
| -rw-r--r-- | gcc/c/c-typeck.c | 2 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/vla-stexp-1.c | 18 |
2 files changed, 19 insertions, 1 deletions
diff --git a/gcc/c/c-typeck.c b/gcc/c/c-typeck.c index 5d6565b..c5bf337 100644 --- a/gcc/c/c-typeck.c +++ b/gcc/c/c-typeck.c @@ -2992,7 +2992,7 @@ c_expr_sizeof_expr (location_t loc, struct c_expr expr) c_last_sizeof_loc = loc; ret.original_code = SIZEOF_EXPR; ret.original_type = NULL; - if (c_vla_type_p (TREE_TYPE (folded_expr))) + if (C_TYPE_VARIABLE_SIZE (TREE_TYPE (folded_expr))) { /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */ ret.value = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (ret.value), diff --git a/gcc/testsuite/gcc.dg/vla-stexp-1.c b/gcc/testsuite/gcc.dg/vla-stexp-1.c new file mode 100644 index 0000000..97d6693 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vla-stexp-1.c @@ -0,0 +1,18 @@ +/* PR29970*/ +/* { dg-do run } */ +/* { dg-options "-Wall -O0" } */ + +int foo(void) +{ + int n = 0; + return sizeof(*({ n = 10; struct foo { int x[n]; } x; &x; })); +} + + +int main() +{ + if (sizeof(struct foo { int x[10]; }) != foo()) + __builtin_abort(); + + return 0; +} |