Reapply r185872 now that the address sanitizer has been changed to support this.

Original commit message:

Stop emitting weak symbols into the "coal" sections.

The Mach-O linker has been able to support the weak-def bit on any symbol for
quite a while now. The compiler however continued to place these symbols into a
"coal" section, which required the linker to map them back to the base section
name.

Replace the sections like this:

  __TEXT/__textcoal_nt   instead use  __TEXT/__text
  __TEXT/__const_coal    instead use  __TEXT/__const
  __DATA/__datacoal_nt   instead use  __DATA/__data

<rdar://problem/14265330>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187939 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index 07cf871..7d9382e 100644
--- a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -524,14 +524,14 @@
 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
                        Mangler *Mang, const TargetMachine &TM) const {
   if (Kind.isText())
-    return GV->isWeakForLinker() ? TextCoalSection : TextSection;
-
-  // If this is weak/linkonce, put this in a coalescable section, either in text
-  // or data depending on if it is writable.
+    return TextSection;
+ 
+  // If this is weak/linkonce, put this in a read only or data section depending
+  // on whether or not it's writable.
   if (GV->isWeakForLinker()) {
     if (Kind.isReadOnly())
-      return ConstTextCoalSection;
-    return DataCoalSection;
+      return ReadOnlySection;
+    return DataSection;
   }
 
   // FIXME: Alignment check should be handled by section classifier.