[LPM] Revert r271781 which was a re-commit of r271652.

There appears to be a strange exception thrown and crash using call_once
on a PPC build bot, and a *really* weird windows link error for
GCMetadata.obj. Still need to investigate the cause of both problems.

Original change summary:
[LPM] Reinstate r271652 to replace the CALL_ONCE_... macro in the legacy
pass manager with the new llvm::call_once facility.

llvm-svn: 271788

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Support/ManagedStatic.cpp b/llvm/lib/Support/ManagedStatic.cpp
index bc4fe954e22..b1feddc09ec 100644
--- a/llvm/lib/Support/ManagedStatic.cpp
+++ b/llvm/lib/Support/ManagedStatic.cpp
@@ -32,7 +32,7 @@ static sys::Mutex* getManagedStaticMutex() {
   // We need to use a function local static here, since this can get called
   // during a static constructor and we need to guarantee that it's initialized
   // correctly.
-  llvm::call_once(mutex_init_flag, initializeMutex);
+  call_once(mutex_init_flag, initializeMutex);
   return ManagedStaticMutex;
 }