Merging r197409:

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r197409 | rikka | 2013-12-16 11:19:18 -0800 (Mon, 16 Dec 2013) | 4 lines

Make Sema::BuildCXXNestedNameSpecifier correctly clear the previous
CXXScopeSpec when necessary while performing typo correction. This fixes
the crash reported in PR18213 (the problem existed since r185487, and
r193020 made it easier to hit).
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git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_34@197463 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 20 insertions, 0 deletions

diff --git a/lib/Sema/SemaCXXScopeSpec.cpp b/lib/Sema/SemaCXXScopeSpec.cpp
index 674411ec06..554a114bae 100644
--- a/lib/Sema/SemaCXXScopeSpec.cpp
+++ b/lib/Sema/SemaCXXScopeSpec.cpp
@@ -497,6 +497,8 @@ bool Sema::BuildCXXNestedNameSpecifier(Scope *S,
         bool DroppedSpecifier =
             Corrected.WillReplaceSpecifier() &&
             Name.getAsString() == Corrected.getAsString(getLangOpts());
+        if (DroppedSpecifier)
+          SS.clear();
         diagnoseTypo(Corrected, PDiag(diag::err_no_member_suggest)
                                   << Name << LookupCtx << DroppedSpecifier
                                   << SS.getRange());
diff --git a/test/SemaCXX/typo-correction-pt2.cpp b/test/SemaCXX/typo-correction-pt2.cpp
index 2da52b31f5..525d11b0a6 100644
--- a/test/SemaCXX/typo-correction-pt2.cpp
+++ b/test/SemaCXX/typo-correction-pt2.cpp
@@ -181,3 +181,21 @@ void test() {
   MessageHeaders::ParseMessageHeaders(5, 4); // expected-error {{no member named 'ParseMessageHeaders' in 'fix_class_name_qualifier::MessageHeaders'; did you mean 'MessageUtils::ParseMessageHeaders'?}}
 }
 }
+
+namespace PR18213 {  // expected-note {{'PR18213' declared here}}
+struct WrapperInfo {
+  int i;
+};
+
+template <typename T> struct Wrappable {
+  static WrapperInfo kWrapperInfo;
+};
+
+// Note the space before "::PR18213" is intended and needed, as it highlights
+// the actual typo, which is the leading "::".
+// TODO: Suggest removing the "::" from "::PR18213" (the right correction)
+// instead of incorrectly suggesting dropping "PR18213::WrapperInfo::".
+template <>
+PR18213::WrapperInfo ::PR18213::Wrappable<int>::kWrapperInfo = { 0 };  // expected-error {{no member named 'PR18213' in 'PR18213::WrapperInfo'; did you mean simply 'PR18213'?}} \
+                                                                       // expected-error {{C++ requires a type specifier for all declarations}}
+}