Switch std::call_once to llvm::call_once

Summary:
The std::call_once implementation in libstdc++ has problems on few systems: NetBSD, OpenBSD and Linux PPC. LLVM ships with a homegrown implementation llvm::call_once to help on these platforms.

This change is required in the NetBSD LLDB port. std::call_once with libstdc++ results with crashing the debugger.

Sponsored by <The NetBSD Foundation>

Reviewers: labath, joerg, emaste, mehdi_amini, clayborg

Reviewed By: labath, clayborg

Subscribers: #lldb

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D29288

llvm-svn: 294202

1 files changed, 4 insertions, 2 deletions

diff --git a/lldb/source/Plugins/Language/ObjC/ObjCLanguage.cpp b/lldb/source/Plugins/Language/ObjC/ObjCLanguage.cpp
index b02d90a0f38..193c5864d01 100644
--- a/lldb/source/Plugins/Language/ObjC/ObjCLanguage.cpp
+++ b/lldb/source/Plugins/Language/ObjC/ObjCLanguage.cpp
@@ -26,6 +26,8 @@
 #include "lldb/Utility/ConstString.h"
 #include "lldb/Utility/StreamString.h"
 
+#include "llvm/Support/Threading.h"
+
 #include "CF.h"
 #include "Cocoa.h"
 #include "CoreMedia.h"
@@ -857,10 +859,10 @@ static void LoadCoreMediaFormatters(TypeCategoryImplSP objc_category_sp) {
 }
 
 lldb::TypeCategoryImplSP ObjCLanguage::GetFormatters() {
-  static std::once_flag g_initialize;
+  static llvm::once_flag g_initialize;
   static TypeCategoryImplSP g_category;
 
-  std::call_once(g_initialize, [this]() -> void {
+  llvm::call_once(g_initialize, [this]() -> void {
     DataVisualization::Categories::GetCategory(GetPluginName(), g_category);
     if (g_category) {
       LoadCoreMediaFormatters(g_category);