https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78284
--- Comment #2 from Martin Sebor <msebor at gcc dot gnu.org> --- Author: msebor Date: Thu Dec 8 23:50:40 2016 New Revision: 243470 URL: https://gcc.gnu.org/viewcvs?rev=243470&root=gcc&view=rev Log: PR c/77531 - __attribute__((alloc_size(1,2))) could also warn on multiplication overflow PR c/78284 - warn on malloc with very large arguments gcc/c-family/ChangeLog: PR c/78284 * c.opt (-Walloc-zero, -Walloc-size-larger-than): New options. gcc/ChangeLog: PR c/78284 * builtin-attrs.def (ATTR_ALLOC_SIZE, ATTR_RETURNS_NONNULL): New identifier tree nodes. (ATTR_ALLOCA_SIZE_1_NOTHROW_LEAF_LIST): New attribute list. (ATTR_MALLOC_SIZE_1_NOTHROW_LIST): Same. (ATTR_MALLOC_SIZE_1_NOTHROW_LEAF_LIST): Same. (ATTR_MALLOC_SIZE_1_2_NOTHROW_LEAF_LIST): Same. (ATTR_ALLOC_SIZE_2_NOTHROW_LEAF_LIST): Same. * builtins.c (expand_builtin_alloca): Call maybe_warn_alloc_args_overflow. * builtins.def (aligned_alloc, calloc, malloc, realloc): Add attribute alloc_size. (alloca): Add attribute alloc_size and returns_nonnull. * calls.h (maybe_warn_alloc_args_overflow): Declare. * calls.c (alloc_max_size, operand_signed_p): New functions. (maybe_warn_alloc_args_overflow): Define. (initialize_argument_information): Diagnose overflow in functions declared with attaribute alloc_size. * doc/invoke.texi (Warning Options): Document -Walloc-zero and -Walloc-size-larger-than. gcc/testsuite/ChangeLog: PR c/78284 * gcc.dg/attr-alloc_size-3.c: New test. * gcc.dg/attr-alloc_size-4.c: New test. * gcc.dg/attr-alloc_size-5.c: New test. * gcc.dg/attr-alloc_size-6.c: New test. * gcc.dg/attr-alloc_size-7.c: New test. * gcc.dg/attr-alloc_size-8.c: New test. * gcc.dg/attr-alloc_size-9.c: New test. * gcc/testsuite/gcc.dg/errno-1.c: Adjust. Added: trunk/gcc/testsuite/gcc.dg/attr-alloc_size-3.c trunk/gcc/testsuite/gcc.dg/attr-alloc_size-4.c trunk/gcc/testsuite/gcc.dg/attr-alloc_size-5.c trunk/gcc/testsuite/gcc.dg/attr-alloc_size-6.c trunk/gcc/testsuite/gcc.dg/attr-alloc_size-7.c trunk/gcc/testsuite/gcc.dg/attr-alloc_size-8.c trunk/gcc/testsuite/gcc.dg/attr-alloc_size-9.c Modified: trunk/gcc/ChangeLog trunk/gcc/builtins.c trunk/gcc/c-family/ChangeLog trunk/gcc/c-family/c.opt trunk/gcc/calls.c trunk/gcc/calls.h trunk/gcc/doc/invoke.texi trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/gcc.dg/errno-1.c