There is only one current section.

Both MCStreamer and MCObjectStreamer were maintaining a current section
variable and they were slightly out of sync. I don't think this was observable,
but was inefficient and error prone.

Changing this requires a few cascading changes:

* SwitchSection has to call ChangeSection earlier for ChangeSection to see
  the old section.
* With that change, ChangeSection cannot call EmitLabel, since during
  ChangeSection we are still in the old section.
* When the object streamer requires a begin label, just reused the existing
  generic support for begin labels instead of calling EmitLabel directly.

llvm-svn: 238357

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/MC/MCMachOStreamer.cpp b/llvm/lib/MC/MCMachOStreamer.cpp
index 6297340..e951073 100644
--- a/llvm/lib/MC/MCMachOStreamer.cpp
+++ b/llvm/lib/MC/MCMachOStreamer.cpp
@@ -162,9 +162,10 @@ void MCMachOStreamer::ChangeSection(MCSection *Section,
 
   // Output a linker-local symbol so we don't need section-relative local
   // relocations. The linker hates us when we do that.
-  if (LabelSections && !HasSectionLabel[Section]) {
+  if (LabelSections && !HasSectionLabel[Section] &&
+      !Section->getBeginSymbol()) {
     MCSymbol *Label = getContext().createLinkerPrivateTempSymbol();
-    EmitLabel(Label);
+    Section->setBeginSymbol(Label);
     HasSectionLabel[Section] = true;
   }
 }