https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95886
--- Comment #8 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-10 branch has been updated by Martin Sebor <mse...@gcc.gnu.org>: https://gcc.gnu.org/g:e4c9aac98611f63847ef6c57916808d9a2d7abcb commit r10-8871-ge4c9aac98611f63847ef6c57916808d9a2d7abcb Author: Martin Sebor <mse...@redhat.com> Date: Thu Oct 8 12:35:01 2020 -0600 Correct handling of constant representations containing embedded nuls (backport from trunk). Resolves: PR middle-end/95189 - memcmp being wrongly stripped like strcm PR middle-end/95886 - suboptimal memcpy with embedded zero bytes gcc/ChangeLog: PR middle-end/95189 PR middle-end/95886 * builtins.c (inline_expand_builtin_string_cmp): Rename... (inline_expand_builtin_bytecmp): ...to this. (builtin_memcpy_read_str): Don't expect data to be nul-terminated. (expand_builtin_memory_copy_args): Handle object representations with embedded nul bytes. (expand_builtin_memcmp): Same. (expand_builtin_strcmp): Adjust call to naming change. (expand_builtin_strncmp): Same. * expr.c (string_constant): Create empty strings with nonzero size. * fold-const.c (c_getstr): Rename locals and update comments. * tree.c (build_string): Accept null pointer argument. (build_string_literal): Same. * tree.h (build_string): Provide a default. (build_string_literal): Same. gcc/testsuite/ChangeLog: PR middle-end/95189 PR middle-end/95886 * gcc.dg/memcmp-pr95189.c: New test. * gcc.dg/strncmp-3.c: New test. * gcc.target/i386/memcpy-pr95886.c: New test.
