From a90ee35a8e245feea5d60639a1d4aba84fa040d7 Mon Sep 17 00:00:00 2001
From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Sun, 11 May 2014 21:25:24 +0000
Subject: [PATCH] PR19713: Don't warn on unused static inline functions, even
 if the 'inline' was implied by 'constexpr'.

llvm-svn: 208511
---
 clang/lib/Sema/SemaDecl.cpp                   |  5 +++--
 clang/test/SemaCXX/warn-unused-filescoped.cpp | 15 +++++++++++++++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index b7c681f08e2e..67c78ce904ad 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -1219,8 +1219,7 @@ bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
         return false;
     } else {
       // 'static inline' functions are defined in headers; don't warn.
-      if (FD->isInlineSpecified() &&
-          !isMainFileLoc(*this, FD->getLocation()))
+      if (FD->isInlined() && !isMainFileLoc(*this, FD->getLocation()))
         return false;
     }
 
@@ -1245,6 +1244,8 @@ bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
   }
 
   // Only warn for unused decls internal to the translation unit.
+  // FIXME: This seems like a bogus check; it suppresses -Wunused-function
+  // for inline functions defined in the main source file, for instance.
   return mightHaveNonExternalLinkage(D);
 }
 
diff --git a/clang/test/SemaCXX/warn-unused-filescoped.cpp b/clang/test/SemaCXX/warn-unused-filescoped.cpp
index b0af5b332270..df4c47e71787 100644
--- a/clang/test/SemaCXX/warn-unused-filescoped.cpp
+++ b/clang/test/SemaCXX/warn-unused-filescoped.cpp
@@ -32,6 +32,13 @@ namespace test7
   inline void bar(int, int) { }
 };
 
+namespace pr19713 {
+#if __cplusplus >= 201103L
+  static constexpr int constexpr1() { return 1; }
+  constexpr int constexpr2() { return 2; }
+#endif
+}
+
 #else
 #define HEADER
 #include "warn-unused-filescoped.cpp"
@@ -193,4 +200,12 @@ void bar() { void func() __attribute__((used)); }
 static void func() {}
 }
 
+namespace pr19713 {
+#if __cplusplus >= 201103L
+  // FIXME: We should warn on both of these.
+  static constexpr int constexpr3() { return 1; } // expected-warning {{unused}}
+  constexpr int constexpr4() { return 2; }
+#endif
+}
+
 #endif