[{"id":3679631,"web_url":"http://patchwork.ozlabs.org/comment/3679631/","msgid":"","list_archive_url":null,"date":"2026-04-20T23:59:32","subject":"Fwd: [PATCH] c-family: Emit -Wsizeof-pointer-memaccess even without\n builtin recognition","submitter":{"id":93197,"url":"http://patchwork.ozlabs.org/api/people/93197/","name":"Naveen Iyer","email":"iyernaveenr@gmail.com"},"content":"Adding CC for relevant maintainers.\n\nThis patch adds a name-based fallback to sizeof_pointer_memaccess_warning\nso that -Wsizeof-pointer-memaccess fires even when -fno-builtin prevents\nbuiltin recognition. Tested with no regressions on x86_64-pc-linux-gnu.\n\nThe original patch is here:\nhttps://gcc.gnu.org/pipermail/gcc-patches/2026-April/713339.html\n\nThanks,\nNaveen\n\n---------- Forwarded message ---------\nFrom: Naveen Iyer \nDate: Mon, Apr 20, 2026 at 6:37 PM\nSubject: [PATCH] c-family: Emit -Wsizeof-pointer-memaccess even without\nbuiltin recognition\nTo: \nCc: Naveen Iyer \n\n\nGCC's -Wsizeof-pointer-memaccess warning does not fire when -fno-builtin\nis used, because sizeof_pointer_memaccess_warning in c-warn.cc bails out\nearly when the callee is not recognized as a built-in via\nfndecl_built_in_p(). This means embedded and freestanding code compiled\nwith -fno-builtin silently misses sizeof(pointer) bugs in memcpy, memset,\nmemmove, and other memory/string function calls.\n\nThis patch adds a fallback path that matches by function name when the\ncallee is not recognized as a built-in, so the diagnostic fires regardless\nof -fno-builtin.\n\nTested on x86_64-pc-linux-gnu with no regressions.\n\nBootstrapped and tested with make check-gcc\nRUNTESTFLAGS=\"dg.exp=Wsizeof-pointer-memaccess*.c\" -- 299 expected passes,\n12 expected failures (all pre-existing), zero unexpected failures.\n\nI believe this qualifies as a small change under the FSF copyright\nassignment exemption. Please let me know if a copyright assignment is\nrequired.\n\nThanks,\nNaveen","headers":{"Return-Path":"","X-Original-To":["incoming@patchwork.ozlabs.org","gcc-patches@gcc.gnu.org"],"Delivered-To":["patchwork-incoming@legolas.ozlabs.org","gcc-patches@gcc.gnu.org"],"Authentication-Results":["legolas.ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=iKC6v6h8;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org\n (client-ip=38.145.34.32; helo=vm01.sourceware.org;\n envelope-from=gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org;\n receiver=patchwork.ozlabs.org)","sourceware.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key,\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=iKC6v6h8","sourceware.org;\n dmarc=pass (p=none dis=none) header.from=gmail.com","sourceware.org; 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Mon, 20 Apr 2026\n 16:59:44 -0700 (PDT)","MIME-Version":"1.0","References":"\n ","In-Reply-To":"\n ","From":"Naveen Iyer ","Date":"Mon, 20 Apr 2026 18:59:32 -0500","X-Gm-Features":"AQROBzC3GfT96AAjYEa3J7bv30Zi36nuKPyiIJkHqAST2gC3NbBBEw_uQgP8PJ0","Message-ID":"\n ","Subject":"Fwd: [PATCH] c-family: Emit -Wsizeof-pointer-memaccess even without\n builtin recognition","To":"gcc-patches@gcc.gnu.org","Cc":"josmyers@redhat.com, polacek@redhat.com, jakub@redhat.com,\n Naveen Iyer ","Content-Type":"multipart/mixed; boundary=\"000000000000bc0ded064fed17e8\"","X-BeenThere":"gcc-patches@gcc.gnu.org","X-Mailman-Version":"2.1.30","Precedence":"list","List-Id":"Gcc-patches mailing list ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org"}}]