Fixed failing assert in code completion.

Summary:
The code was accessing uninstantiated default argument.
This resulted in failing assertion at ParmVarDecl::getDefaultArg().

Reviewers: erikjv, klimek, bkramer, krasimir

Reviewed By: krasimir

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D35682

llvm-svn: 308722

2 files changed, 14 insertions, 4 deletions

diff --git a/clang/lib/Sema/SemaCodeComplete.cpp b/clang/lib/Sema/SemaCodeComplete.cpp
index 91a8c619b26..4de7d422072 100644
--- a/clang/lib/Sema/SemaCodeComplete.cpp
+++ b/clang/lib/Sema/SemaCodeComplete.cpp
@@ -2401,10 +2401,7 @@ formatBlockPlaceholder(const PrintingPolicy &Policy, const NamedDecl *BlockDecl,
 static std::string GetDefaultValueString(const ParmVarDecl *Param,
                                          const SourceManager &SM,
                                          const LangOptions &LangOpts) {
-  const Expr *defaultArg = Param->getDefaultArg();
-  if (!defaultArg)
-    return "";
-  const SourceRange SrcRange = defaultArg->getSourceRange();
+  const SourceRange SrcRange = Param->getDefaultArgRange();
   CharSourceRange CharSrcRange = CharSourceRange::getTokenRange(SrcRange);
   bool Invalid = CharSrcRange.isInvalid();
   if (Invalid)
diff --git a/clang/test/CodeCompletion/uninstantiated_params.cpp b/clang/test/CodeCompletion/uninstantiated_params.cpp
new file mode 100644
index 00000000000..57a520dd571
--- /dev/null
+++ b/clang/test/CodeCompletion/uninstantiated_params.cpp
@@ -0,0 +1,13 @@
+template <class T>
+struct unique_ptr {
+  typedef T* pointer;
+
+  void reset(pointer ptr = pointer());
+};
+
+void test() {
+  unique_ptr<int> x;
+  x.
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-at=%s:10:5 %s -o - | FileCheck -check-prefix=CHECK-CC1 %s
+  // CHECK-CC1: [#void#]reset({#<#unique_ptr<int>::pointer ptr = pointer()#>#})
+}