diff --git a/clang/lib/Basic/Targets.cpp b/clang/lib/Basic/Targets.cpp
index 3bf20fef5d22..a3b8330707b9 100644
--- a/clang/lib/Basic/Targets.cpp
+++ b/clang/lib/Basic/Targets.cpp
@@ -4734,9 +4734,6 @@ protected:
 
     Builder.defineMacro("__rtems__");
     Builder.defineMacro("__ELF__");
-    // Required by the libc++ locale support.
-    if (Opts.CPlusPlus)
-      Builder.defineMacro("_GNU_SOURCE");
   }
 
 public:
diff --git a/clang/test/Preprocessor/init.c b/clang/test/Preprocessor/init.c
index f7540a6322fe..0bd9e9784599 100644
--- a/clang/test/Preprocessor/init.c
+++ b/clang/test/Preprocessor/init.c
@@ -8779,7 +8779,6 @@
 // KFREEBSDI686-DEFINE:#define __GLIBC__ 1
 //
 // RUN: %clang_cc1 -x c++ -triple i686-pc-linux-gnu -fobjc-runtime=gcc -E -dM < /dev/null | FileCheck -match-full-lines -check-prefix GNUSOURCE %s
-// RUN: %clang_cc1 -x c++ -triple sparc-rtems-elf -E -dM < /dev/null | FileCheck -match-full-lines -check-prefix GNUSOURCE %s
 // GNUSOURCE:#define _GNU_SOURCE 1
 //
 // RUN: %clang_cc1 -x c++ -std=c++98 -fno-rtti -E -dM < /dev/null | FileCheck -match-full-lines -check-prefix NORTTI %s