[clang-tidy] Fix for llvm.org/PR23161

The misc-static-assert check will not warn on the followings:
  assert("Some message" == NULL);
  assert(NULL == "Some message");

llvm-svn: 234596

1 files changed, 12 insertions, 8 deletions

diff --git a/clang-tools-extra/clang-tidy/misc/StaticAssertCheck.cpp b/clang-tools-extra/clang-tidy/misc/StaticAssertCheck.cpp
index 91451e6..c63cd74 100644
--- a/clang-tools-extra/clang-tidy/misc/StaticAssertCheck.cpp
+++ b/clang-tools-extra/clang-tidy/misc/StaticAssertCheck.cpp
@@ -27,15 +27,17 @@ StaticAssertCheck::StaticAssertCheck(StringRef Name, ClangTidyContext *Context)
     : ClangTidyCheck(Name, Context) {}
 
 void StaticAssertCheck::registerMatchers(MatchFinder *Finder) {
-  auto IsAlwaysFalse = ignoringParenImpCasts(
-      anyOf(boolLiteral(equals(false)).bind("isAlwaysFalse"),
-            integerLiteral(equals(0)).bind("isAlwaysFalse")));
+  auto IsAlwaysFalse = expr(ignoringParenImpCasts(
+      expr(anyOf(boolLiteral(equals(false)), integerLiteral(equals(0)),
+          nullPtrLiteralExpr())).bind("isAlwaysFalse")));
+  auto IsAlwaysFalseWithCast = ignoringParenImpCasts(anyOf(IsAlwaysFalse,
+      cStyleCastExpr(has(IsAlwaysFalse)).bind("castExpr")));
   auto AssertExprRoot = anyOf(
       binaryOperator(
-          hasOperatorName("&&"),
+          anyOf(hasOperatorName("&&"), hasOperatorName("==")),
           hasEitherOperand(ignoringImpCasts(stringLiteral().bind("assertMSG"))),
-          anyOf(binaryOperator(hasEitherOperand(IsAlwaysFalse)), anything()))
-          .bind("assertExprRoot"),
+          anyOf(binaryOperator(hasEitherOperand(IsAlwaysFalseWithCast)),
+          anything())).bind("assertExprRoot"),
       IsAlwaysFalse);
   auto Condition = expr(anyOf(
       expr(ignoringParenCasts(anyOf(
@@ -60,6 +62,7 @@ void StaticAssertCheck::check(const MatchFinder::MatchResult &Result) {
   const auto *AssertMSG = Result.Nodes.getNodeAs<StringLiteral>("assertMSG");
   const auto *AssertExprRoot =
       Result.Nodes.getNodeAs<BinaryOperator>("assertExprRoot");
+  const auto *CastExpr = Result.Nodes.getNodeAs<CStyleCastExpr>("castExpr");
   SourceLocation AssertExpansionLoc = CondStmt->getLocStart();
 
   if (!Opts.CPlusPlus11 || !AssertExpansionLoc.isValid() ||
@@ -75,7 +78,7 @@ void StaticAssertCheck::check(const MatchFinder::MatchResult &Result) {
     return;
 
   // False literal is not the result of macro expansion.
-  if (IsAlwaysFalse) {
+  if (IsAlwaysFalse && (!CastExpr || CastExpr->getType()->isPointerType())) {
     SourceLocation FalseLiteralLoc =
         SM.getImmediateSpellingLoc(IsAlwaysFalse->getExprLoc());
     if (!FalseLiteralLoc.isMacroID())
@@ -83,7 +86,8 @@ void StaticAssertCheck::check(const MatchFinder::MatchResult &Result) {
 
     StringRef FalseMacroName =
         Lexer::getImmediateMacroName(FalseLiteralLoc, SM, Opts);
-    if (FalseMacroName.compare_lower("false") == 0)
+    if (FalseMacroName.compare_lower("false") == 0 ||
+        FalseMacroName.compare_lower("null") == 0)
       return;
   }