From c77c8e95e3f3a3f9161da179abf4b59f5dc78e74 Mon Sep 17 00:00:00 2001 From: Nick Lewycky Date: Wed, 23 Jan 2013 05:08:29 +0000 Subject: [PATCH] Make __attribute__((nonnull)) use the general expression evaluator to search for nulls instead of limiting itself to the language-defined "null pointer constant". llvm-svn: 173227 --- clang/lib/Sema/SemaChecking.cpp | 16 ++++++++++++++-- clang/test/SemaCXX/attr-nonnull.cpp | 9 +++++++++ 2 files changed, 23 insertions(+), 2 deletions(-) diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp index 3d4c5d3..0d8f764 100644 --- a/clang/lib/Sema/SemaChecking.cpp +++ b/clang/lib/Sema/SemaChecking.cpp @@ -1837,8 +1837,20 @@ Sema::CheckNonNullArguments(const NonNullAttr *NonNull, e = NonNull->args_end(); i != e; ++i) { const Expr *ArgExpr = ExprArgs[*i]; - if (ArgExpr->isNullPointerConstant(Context, - Expr::NPC_ValueDependentIsNotNull)) + + // As a special case, transparent unions initialized with zero are + // considered null for the purposes of the nonnull attribute. + if (const RecordType *UT = ArgExpr->getType()->getAsUnionType()) { + if (UT->getDecl()->hasAttr()) + if (const CompoundLiteralExpr *CLE = + dyn_cast(ArgExpr)) + if (const InitListExpr *ILE = + dyn_cast(CLE->getInitializer())) + ArgExpr = ILE->getInit(0); + } + + bool Result; + if (ArgExpr->EvaluateAsBooleanCondition(Result, Context) && !Result) Diag(CallSiteLoc, diag::warn_null_arg) << ArgExpr->getSourceRange(); } } diff --git a/clang/test/SemaCXX/attr-nonnull.cpp b/clang/test/SemaCXX/attr-nonnull.cpp index 09c054c..76e1b74 100644 --- a/clang/test/SemaCXX/attr-nonnull.cpp +++ b/clang/test/SemaCXX/attr-nonnull.cpp @@ -31,3 +31,12 @@ namespace rdar8769025 { f2(0, 0); // expected-warning{{null passed to a callee which requires a non-null argument}} } } + +namespace test3 { +__attribute__((nonnull(1))) void f(void *ptr); + +void g() { + f(static_cast((void*)0)); // expected-warning{{null passed}} + f(static_cast(0)); // expected-warning{{null passed}} +} +} -- 2.7.4