https://github.com/tbaederr updated https://github.com/llvm/llvm-project/pull/174187
>From 1f02a45a56838ad3542b2b15b14c1ae8bb7bb7e2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timm=20B=C3=A4der?= <[email protected]> Date: Fri, 2 Jan 2026 09:29:56 +0100 Subject: [PATCH] [clang][bytecode] Check builtin_memchr() for one-past-end pointers We can't read from them and this fails later. Fixes #173942 --- clang/lib/AST/ByteCode/InterpBuiltin.cpp | 5 +++++ clang/test/AST/ByteCode/builtin-functions.cpp | 4 ++++ 2 files changed, 9 insertions(+) diff --git a/clang/lib/AST/ByteCode/InterpBuiltin.cpp b/clang/lib/AST/ByteCode/InterpBuiltin.cpp index 65101174247d1..065870c5c0ab5 100644 --- a/clang/lib/AST/ByteCode/InterpBuiltin.cpp +++ b/clang/lib/AST/ByteCode/InterpBuiltin.cpp @@ -73,6 +73,8 @@ static bool isReadable(const Pointer &P) { return false; if (!P.isLive()) return false; + if (P.isOnePastEnd()) + return false; return true; } @@ -2089,6 +2091,9 @@ static bool interp__builtin_memchr(InterpState &S, CodePtr OpPC, return false; } + if (!isReadable(Ptr)) + return false; + if (ID == Builtin::BIstrchr || ID == Builtin::BI__builtin_strchr) { int64_t DesiredTrunc; if (S.getASTContext().CharTy->isSignedIntegerType()) diff --git a/clang/test/AST/ByteCode/builtin-functions.cpp b/clang/test/AST/ByteCode/builtin-functions.cpp index 3076b5239ebbe..3cde5a2b42e3d 100644 --- a/clang/test/AST/ByteCode/builtin-functions.cpp +++ b/clang/test/AST/ByteCode/builtin-functions.cpp @@ -1649,6 +1649,10 @@ namespace Memchr { return __builtin_char_memchr(c + 1, 'f', 1) == nullptr; } static_assert(f()); + + + extern const char char_memchr_arg[0l]; + char *memchr_result = __builtin_char_memchr(char_memchr_arg, 123, 32); } namespace Strchr { _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
