llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang-analysis Author: Ziqing Luo (ziqingluo-90) <details> <summary>Changes</summary> - Fix a bug in UnsafeBufferUsage.cpp related to casting to PointerType (report by @<!-- -->hnrklssn [here](https://github.com/llvm/llvm-project/pull/101583#discussion_r1767705992)) - Suppress -Wunsafe-buffer-usage-in-libc-call for C files --- Full diff: https://github.com/llvm/llvm-project/pull/109496.diff 3 Files Affected: - (modified) clang/lib/Analysis/UnsafeBufferUsage.cpp (+5-3) - (modified) clang/lib/Sema/AnalysisBasedWarnings.cpp (+4-2) - (added) clang/test/SemaCXX/warn-unsafe-buffer-usage-no-libc-functions-in-c.c (+9) ``````````diff diff --git a/clang/lib/Analysis/UnsafeBufferUsage.cpp b/clang/lib/Analysis/UnsafeBufferUsage.cpp index a16762244b1766..110a121e71a7d2 100644 --- a/clang/lib/Analysis/UnsafeBufferUsage.cpp +++ b/clang/lib/Analysis/UnsafeBufferUsage.cpp @@ -250,7 +250,9 @@ AST_MATCHER_P(Stmt, ignoreUnsafeBufferInContainer, AST_MATCHER_P(Stmt, ignoreUnsafeLibcCall, const UnsafeBufferUsageHandler *, Handler) { - return Handler->ignoreUnsafeBufferInLibcCall(Node.getBeginLoc()); + if (Finder->getASTContext().getLangOpts().CPlusPlus) + return Handler->ignoreUnsafeBufferInLibcCall(Node.getBeginLoc()); + return true; /* Only warn about libc calls for C++ */ } AST_MATCHER_P(CastExpr, castSubExpr, internal::Matcher<Expr>, innerMatcher) { @@ -789,7 +791,7 @@ AST_MATCHER_P(CallExpr, hasUnsafePrintfStringArg, if (!FristParmTy->isPointerType()) return false; // possibly some user-defined printf function - QualType FirstPteTy = (cast<PointerType>(FristParmTy))->getPointeeType(); + QualType FirstPteTy = FristParmTy->getAs<PointerType>()->getPointeeType(); if (!Ctx.getFILEType() .isNull() && //`FILE *` must be in the context if it is fprintf @@ -865,7 +867,7 @@ AST_MATCHER(CallExpr, hasUnsafeSnprintfBuffer) { if (!FirstParmTy->isPointerType()) return false; // Not an snprint - QualType FirstPteTy = cast<PointerType>(FirstParmTy)->getPointeeType(); + QualType FirstPteTy = FirstParmTy->getAs<PointerType>()->getPointeeType(); const Expr *Buf = Node.getArg(0), *Size = Node.getArg(1); if (FirstPteTy.isConstQualified() || !Buf->getType()->isPointerType() || diff --git a/clang/lib/Sema/AnalysisBasedWarnings.cpp b/clang/lib/Sema/AnalysisBasedWarnings.cpp index 117b2c8bc57935..724b543cdf882c 100644 --- a/clang/lib/Sema/AnalysisBasedWarnings.cpp +++ b/clang/lib/Sema/AnalysisBasedWarnings.cpp @@ -2549,6 +2549,7 @@ void clang::sema::AnalysisBasedWarnings::IssueWarnings( DiagnosticOptions &DiagOpts = Diags.getDiagnosticOptions(); // UnsafeBufferUsage analysis settings. + bool IsCXXLang = S.getLangOpts().CPlusPlus; bool UnsafeBufferUsageCanEmitSuggestions = S.getLangOpts().CPlusPlus20; bool UnsafeBufferUsageShouldEmitSuggestions = // Should != Can. UnsafeBufferUsageCanEmitSuggestions && @@ -2567,8 +2568,9 @@ void clang::sema::AnalysisBasedWarnings::IssueWarnings( Node->getBeginLoc()) || !Diags.isIgnored(diag::warn_unsafe_buffer_usage_in_container, Node->getBeginLoc()) || - !Diags.isIgnored(diag::warn_unsafe_buffer_libc_call, - Node->getBeginLoc())) { + (!Diags.isIgnored(diag::warn_unsafe_buffer_libc_call, + Node->getBeginLoc()) && + IsCXXLang /* we only warn about libc calls in C++ files */)) { clang::checkUnsafeBufferUsage(Node, R, UnsafeBufferUsageShouldEmitSuggestions); } diff --git a/clang/test/SemaCXX/warn-unsafe-buffer-usage-no-libc-functions-in-c.c b/clang/test/SemaCXX/warn-unsafe-buffer-usage-no-libc-functions-in-c.c new file mode 100644 index 00000000000000..e305c3e140dff9 --- /dev/null +++ b/clang/test/SemaCXX/warn-unsafe-buffer-usage-no-libc-functions-in-c.c @@ -0,0 +1,9 @@ +// RUN: %clang_cc1 -Wunsafe-buffer-usage %s -verify %s + +void* memcpy(void *dst,const void *src, unsigned long size); + +void f(int *p, int *q) { + + memcpy(p, q, 10); // no libc warn in C + ++p[5]; // expected-warning{{unsafe buffer access}} +} `````````` </details> https://github.com/llvm/llvm-project/pull/109496 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
