diff --git a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index 55e175680be..8820d10a0c6 100644
--- a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -626,7 +626,9 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
           cast<GlobalVariable>(GV)) < 32)
     return UStringSection;
 
-  if (Kind.isMergeableConst()) {
+  // With MachO only variables whose corresponding symbol starts with 'l' or
+  // 'L' can be merged, so we only try merging GVs with private linkage.
+  if (GV->hasPrivateLinkage() && Kind.isMergeableConst()) {
     if (Kind.isMergeableConst4())
       return FourByteConstantSection;
     if (Kind.isMergeableConst8())
diff --git a/test/CodeGen/X86/global-sections.ll b/test/CodeGen/X86/global-sections.ll
index c763f3947e5..fa1169d8a8e 100644
--- a/test/CodeGen/X86/global-sections.ll
+++ b/test/CodeGen/X86/global-sections.ll
@@ -53,21 +53,20 @@ define void @F1() {
 
 
 ; _Complex long long const G4 = 34;
-@G4 = unnamed_addr constant {i64,i64} { i64 34, i64 0 }
+@G4 = private unnamed_addr constant {i64,i64} { i64 34, i64 0 }
 
 ; DARWIN: .section        __TEXT,__literal16,16byte_literals
-; DARWIN: _G4:
+; DARWIN: L_G4:
 ; DARWIN:     .long 34
 
 ; DARWIN-STATIC: .section        __TEXT,__literal16,16byte_literals
-; DARWIN-STATIC: _G4:
+; DARWIN-STATIC: L_G4:
 ; DARWIN-STATIC:     .long 34
 
 ; DARWIN64: .section        __TEXT,__literal16,16byte_literals
-; DARWIN64: _G4:
+; DARWIN64: L_G4:
 ; DARWIN64:     .quad 34
 
-
 ; int G5 = 47;
 @G5 = global i32 47
 
@@ -194,3 +193,23 @@ define void @F1() {
 ; WIN32-SECTIONS: L_G14:
 ; WIN32-SECTIONS:        .asciz  "foo"
 
+; cannot be merged on MachO, but can on other formats.
+@G15 = unnamed_addr constant i64 0
+
+; LINUX: .section        .rodata.cst8,"aM",@progbits,8
+; LINUX: G15:
+
+; DARWIN: .section      __TEXT,__const
+; DARWIN: _G15:
+
+; DARWIN-STATIC: .section       __TEXT,__const
+; DARWIN-STATIC: _G15:
+
+; DARWIN64: .section       __TEXT,__const
+; DARWIN64: _G15:
+
+; LINUX-SECTIONS: .section      .rodata.G15,"aM",@progbits,8
+; LINUX-SECTIONS: G15:
+
+; WIN32-SECTIONS: .section      .rdata,"rd",one_only,_G15
+; WIN32-SECTIONS: _G15: