diff options
Diffstat (limited to 'gcc/c-family/c-warn.c')
| -rw-r--r-- | gcc/c-family/c-warn.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/gcc/c-family/c-warn.c b/gcc/c-family/c-warn.c index 859d72b..95ac09d 100644 --- a/gcc/c-family/c-warn.c +++ b/gcc/c-family/c-warn.c @@ -792,13 +792,26 @@ sizeof_pointer_memaccess_warning (location_t *sizeof_arg_loc, tree callee, { /* The argument type may be an array. Diagnose bounded string copy functions that specify the bound in terms of the source - argument rather than the destination. */ + argument rather than the destination unless they are equal + to one another. Handle constant sizes and also try to handle + sizeof expressions involving VLAs. */ if (strop && !cmp && fncode != BUILT_IN_STRNDUP && src) { tem = tree_strip_nop_conversions (src); if (TREE_CODE (tem) == ADDR_EXPR) tem = TREE_OPERAND (tem, 0); - if (operand_equal_p (tem, sizeof_arg[idx], OEP_ADDRESS_OF)) + + tree d = tree_strip_nop_conversions (dest); + if (TREE_CODE (d) == ADDR_EXPR) + d = TREE_OPERAND (d, 0); + + tree dstsz = TYPE_SIZE_UNIT (TREE_TYPE (d)); + tree srcsz = TYPE_SIZE_UNIT (TREE_TYPE (tem)); + + if ((!dstsz + || !srcsz + || !operand_equal_p (dstsz, srcsz, OEP_LEXICOGRAPHIC)) + && operand_equal_p (tem, sizeof_arg[idx], OEP_ADDRESS_OF)) warning_at (sizeof_arg_loc[idx], OPT_Wsizeof_pointer_memaccess, "argument to %<sizeof%> in %qD call is the same " "expression as the source; did you mean to use " |