From: David Majnemer <david.majnemer@gmail.com>
Date: Fri, 9 Jan 2015 05:10:55 +0000 (+0000)
Subject: Parse: Don't crash when trailing return type is missing
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=47c0b41f008e1f8403392ae4781e88c00b366be4;p=clang

Parse: Don't crash when trailing return type is missing

Sema::CheckParmsForFunctionDef can't cope with a null TypeSourceInfo.
Don't let the AST contain the malformed lambda.

This fixes PR22122.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@225505 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Parse/ParseExprCXX.cpp b/lib/Parse/ParseExprCXX.cpp
index f101d9f127..355503caa9 100644
--- a/lib/Parse/ParseExprCXX.cpp
+++ b/lib/Parse/ParseExprCXX.cpp
@@ -1052,6 +1052,7 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer(
   TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
   Actions.PushLambdaScope();    
 
+  TypeResult TrailingReturnType;
   if (Tok.is(tok::l_paren)) {
     ParseScope PrototypeScope(this,
                               Scope::FunctionPrototypeScope |
@@ -1112,7 +1113,6 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer(
     SourceLocation FunLocalRangeEnd = DeclEndLoc;
 
     // Parse trailing-return-type[opt].
-    TypeResult TrailingReturnType;
     if (Tok.is(tok::arrow)) {
       FunLocalRangeEnd = Tok.getLocation();
       SourceRange Range;
@@ -1182,12 +1182,11 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer(
     MaybeParseCXX11Attributes(Attr, &DeclEndLoc);
 
     // Parse the return type, if there is one.
-    TypeResult TrailingReturnType;
     if (Tok.is(tok::arrow)) {
       SourceRange Range;
       TrailingReturnType = ParseTrailingReturnType(Range);
       if (Range.getEnd().isValid())
-        DeclEndLoc = Range.getEnd();      
+        DeclEndLoc = Range.getEnd();
     }
 
     SourceLocation NoLoc;
@@ -1235,9 +1234,9 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer(
   StmtResult Stmt(ParseCompoundStatementBody());
   BodyScope.Exit();
 
-  if (!Stmt.isInvalid())
+  if (!Stmt.isInvalid() && !TrailingReturnType.isInvalid())
     return Actions.ActOnLambdaExpr(LambdaBeginLoc, Stmt.get(), getCurScope());
- 
+
   Actions.ActOnLambdaError(LambdaBeginLoc, getCurScope());
   return ExprError();
 }
diff --git a/test/Parser/cxx0x-lambda-expressions.cpp b/test/Parser/cxx0x-lambda-expressions.cpp
index 8cfe7f3b02..4bcc60c73c 100644
--- a/test/Parser/cxx0x-lambda-expressions.cpp
+++ b/test/Parser/cxx0x-lambda-expressions.cpp
@@ -91,3 +91,10 @@ class C {
       __attribute__((noreturn)) { while(1); }; // expected-error {{expected body of lambda expression}}
   }
 };
+
+template <typename>
+void PR22122() {
+  [](int) -> {}; // expected-error {{expected a type}}
+}
+
+template void PR22122<int>();