From 71729a81a12da342e4a5a81f0984052b145f1c12 Mon Sep 17 00:00:00 2001
From: Nico Weber <nicolasweber@gmx.de>
Date: Sun, 4 Jan 2015 20:32:12 +0000
Subject: [PATCH] Remove an assert that's not true on invalid code.

r185773 added an assert that checked that a CXXUnresolvedConstructExpr either
has a valid rparen, or exactly one argument.  This doesn't have to be true for
invalid inputs.  Convert the assert to an if, and add a test for this case.

Found by SLi's afl bot.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@225140 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/AST/ExprCXX.h    |  5 +++--
 test/Misc/ast-dump-invalid.cpp | 20 ++++++++++++++++++++
 test/SemaCXX/return.cpp        |  8 ++++++++
 3 files changed, 31 insertions(+), 2 deletions(-)
 create mode 100644 test/Misc/ast-dump-invalid.cpp

diff --git a/include/clang/AST/ExprCXX.h b/include/clang/AST/ExprCXX.h
index 040fbe7f92..aa33b61d7c 100644
--- a/include/clang/AST/ExprCXX.h
+++ b/include/clang/AST/ExprCXX.h
@@ -2915,8 +2915,9 @@ public:
 
   SourceLocation getLocStart() const LLVM_READONLY;
   SourceLocation getLocEnd() const LLVM_READONLY {
-    assert(RParenLoc.isValid() || NumArgs == 1);
-    return RParenLoc.isValid() ? RParenLoc : getArg(0)->getLocEnd();
+    if (!RParenLoc.isValid() && NumArgs > 0)
+      return getArg(NumArgs - 1)->getLocEnd();
+    return RParenLoc;
   }
 
   static bool classof(const Stmt *T) {
diff --git a/test/Misc/ast-dump-invalid.cpp b/test/Misc/ast-dump-invalid.cpp
new file mode 100644
index 0000000000..3b97cc6540
--- /dev/null
+++ b/test/Misc/ast-dump-invalid.cpp
@@ -0,0 +1,20 @@
+// RUN: not %clang_cc1 -std=c++11 -triple x86_64-linux-gnu -fms-extensions -ast-dump -ast-dump-filter Test %s | FileCheck -check-prefix CHECK -strict-whitespace %s
+
+namespace TestInvalidRParenOnCXXUnresolvedConstructExpr {
+template <class T>
+void f(T i, T j) {
+  return T (i, j;
+}
+}
+
+// CHECK: NamespaceDecl {{.*}} <{{.*}}> {{.*}} TestInvalidRParenOnCXXUnresolvedConstructExpr
+// CHECK-NEXT: `-FunctionTemplateDecl
+// CHECK-NEXT:   |-TemplateTypeParmDecl
+// CHECK-NEXT:   `-FunctionDecl
+// CHECK-NEXT:     |-ParmVarDecl
+// CHECK-NEXT:     |-ParmVarDecl
+// CHECK-NEXT:     `-CompoundStmt
+// CHECK-NEXT:       `-ReturnStmt
+// CHECK-NEXT:         `-CXXUnresolvedConstructExpr {{.*}} <col:10, col:16> 'T'
+// CHECK-NEXT:           |-DeclRefExpr {{.*}} <col:13> 'T' lvalue ParmVar {{.*}} 'i' 'T'
+// CHECK-NEXT:           `-DeclRefExpr {{.*}} <col:16> 'T' lvalue ParmVar {{.*}} 'j' 'T'
diff --git a/test/SemaCXX/return.cpp b/test/SemaCXX/return.cpp
index 98dbd51f58..8c1664516a 100644
--- a/test/SemaCXX/return.cpp
+++ b/test/SemaCXX/return.cpp
@@ -112,3 +112,11 @@ namespace ctor_returns_void {
     ~S() { return f(); } // expected-error {{destructor '~S' must not return void expression}}
   };
 }
+
+void cxx_unresolved_expr() {
+  // The use of an undeclared variable tricks clang into building a
+  // CXXUnresolvedConstructExpr, and the missing ')' gives it an invalid source
+  // location for its rparen.  Check that emitting a diag on the range of the
+  // expr doesn't assert.
+  return int(undeclared, 4; // expected-error {{expected ')'}} expected-note{{to match this '('}} expected-error {{void function 'cxx_unresolved_expr' should not return a value}} expected-error {{use of undeclared identifier 'undeclared'}}
+}
-- 
2.40.0