https://github.com/venk-ks updated https://github.com/llvm/llvm-project/pull/168965
>From e87a76909a05e83a653281f6142b4d01667adad0 Mon Sep 17 00:00:00 2001 From: Venkatesh Srinivasan <[email protected]> Date: Thu, 20 Nov 2025 22:12:18 +0000 Subject: [PATCH] [Clang][Sema] Add fortify warnings for strcat --- clang/lib/Sema/SemaChecking.cpp | 3 +++ clang/test/Sema/warn-fortify-source.c | 8 ++++++++ 2 files changed, 11 insertions(+) diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp index 3e1edc4548034..f4e58de91286b 100644 --- a/clang/lib/Sema/SemaChecking.cpp +++ b/clang/lib/Sema/SemaChecking.cpp @@ -1263,6 +1263,8 @@ void Sema::checkFortifiedBuiltinMemoryFunction(FunctionDecl *FD, switch (BuiltinID) { default: return; + case Builtin::BI__builtin_strcat: + case Builtin::BIstrcat: case Builtin::BI__builtin_stpcpy: case Builtin::BIstpcpy: case Builtin::BI__builtin_strcpy: @@ -1273,6 +1275,7 @@ void Sema::checkFortifiedBuiltinMemoryFunction(FunctionDecl *FD, break; } + case Builtin::BI__builtin___strcat_chk: case Builtin::BI__builtin___stpcpy_chk: case Builtin::BI__builtin___strcpy_chk: { DiagID = diag::warn_fortify_strlen_overflow; diff --git a/clang/test/Sema/warn-fortify-source.c b/clang/test/Sema/warn-fortify-source.c index 216878c0836d8..750bd5361ade9 100644 --- a/clang/test/Sema/warn-fortify-source.c +++ b/clang/test/Sema/warn-fortify-source.c @@ -76,6 +76,14 @@ void call_strcpy_nowarn(void) { __builtin_strcpy(dst, src); } +void call_strcat(void) { + const char *const src = "abcd"; + char dst1[5]; + char dst2[4]; + __builtin_strcat(dst1, src); + __builtin_strcat(dst2, src); // expected-warning {{'strcat' will always overflow; destination buffer has size 4, but the source string has length 5 (including NUL byte)}} +} + void call_stpcpy(void) { const char *const src = "abcd"; char dst1[5]; _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
