From a08fcb8105bf53f3640ad17f61bdcde2d8ace78a Mon Sep 17 00:00:00 2001
From: Hans Wennborg <hans@hanshq.net>
Date: Fri, 3 Jun 2011 17:37:26 +0000
Subject: [PATCH] Make -Wignored-qualifiers point to the first ignored
 qualifier.

In code such as "char* volatile const j()", Clang warns that "volatile
const" will be ignored. Make it point to the first ignored qualifier,
and simplify the code a bit.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@132563 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaType.cpp   | 28 ++++++++++++----------------
 test/SemaCXX/return.cpp |  5 +++++
 2 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index 3c4e09ae86..e7f9885698 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -1480,41 +1480,37 @@ static void DiagnoseIgnoredQualifiers(unsigned Quals,
   FixItHint VolatileFixIt;
   FixItHint RestrictFixIt;
 
+  const SourceManager &SM = S.getSourceManager();
+
   // FIXME: The locations here are set kind of arbitrarily. It'd be nicer to
   // find a range and grow it to encompass all the qualifiers, regardless of
   // the order in which they textually appear.
   if (Quals & Qualifiers::Const) {
     ConstFixIt = FixItHint::CreateRemoval(ConstQualLoc);
-    Loc = ConstQualLoc;
-    ++NumQuals;
     QualStr = "const";
+    ++NumQuals;
+    if (!Loc.isValid() || SM.isBeforeInTranslationUnit(ConstQualLoc, Loc))
+      Loc = ConstQualLoc;
   }
   if (Quals & Qualifiers::Volatile) {
     VolatileFixIt = FixItHint::CreateRemoval(VolatileQualLoc);
-    if (NumQuals == 0) {
-      Loc = VolatileQualLoc;
-      QualStr = "volatile";
-    } else {
-      QualStr += " volatile";
-    }
+    QualStr += (NumQuals == 0 ? "volatile" : " volatile");
     ++NumQuals;
+    if (!Loc.isValid() || SM.isBeforeInTranslationUnit(VolatileQualLoc, Loc))
+      Loc = VolatileQualLoc;
   }
   if (Quals & Qualifiers::Restrict) {
     RestrictFixIt = FixItHint::CreateRemoval(RestrictQualLoc);
-    if (NumQuals == 0) {
-      Loc = RestrictQualLoc;
-      QualStr = "restrict";
-    } else {
-      QualStr += " restrict";
-    }
+    QualStr += (NumQuals == 0 ? "restrict" : " restrict");
     ++NumQuals;
+    if (!Loc.isValid() || SM.isBeforeInTranslationUnit(RestrictQualLoc, Loc))
+      Loc = RestrictQualLoc;
   }
 
   assert(NumQuals > 0 && "No known qualifiers?");
 
   S.Diag(Loc, diag::warn_qual_return_type)
-    << QualStr << NumQuals
-    << ConstFixIt << VolatileFixIt << RestrictFixIt;
+    << QualStr << NumQuals << ConstFixIt << VolatileFixIt << RestrictFixIt;
 }
 
 /// GetTypeForDeclarator - Convert the type for the specified
diff --git a/test/SemaCXX/return.cpp b/test/SemaCXX/return.cpp
index f83b55a6ab..b457f6ace5 100644
--- a/test/SemaCXX/return.cpp
+++ b/test/SemaCXX/return.cpp
@@ -39,6 +39,11 @@ g();
 char* const h(); // expected-warning{{'const' type qualifier on return type has no effect}}
 char* volatile i(); // expected-warning{{'volatile' type qualifier on return type has no effect}}
 
+char*
+volatile // expected-warning{{'const volatile' type qualifiers on return type have no effect}}
+const
+j();
+
 const volatile int scalar_cv(); // expected-warning{{'const volatile' type qualifiers on return type have no effect}}
 }
 
-- 
2.40.0