From 11f8aeac127c6f560fb1f1c9de7f5d2eb73600f3 Mon Sep 17 00:00:00 2001
From: Sergiu Deitsch <sergiu.deitsch@gmail.com>
Date: Tue, 15 Jun 2021 18:30:44 +0200
Subject: [PATCH] cmake: export `<atomic>` availability (fixes #667)

---
 CMakeLists.txt        | 6 +++++-
 bazel/glog.bzl        | 1 +
 src/glog/logging.h.in | 2 +-
 3 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 70050037c..e68261c99 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -398,6 +398,10 @@ if (HAVE_EXECINFO_H)
   set (HAVE_STACKTRACE 1)
 endif (HAVE_EXECINFO_H)
 
+if (HAVE_CXX11_ATOMIC)
+  set (ac_cv_cxx11_atomic 1)
+endif (HAVE_CXX11_ATOMIC)
+
 if (WITH_SYMBOLIZE)
   if (WIN32 OR CYGWIN)
     cmake_push_check_state (RESET)
@@ -466,7 +470,7 @@ else (WITH_THREADS AND Threads_FOUND)
   set (NO_THREADS 1)
 endif (WITH_THREADS AND Threads_FOUND)
 
-# fopen/open on Cygwin can not handle unix-type paths like /home/.... 
+# fopen/open on Cygwin can not handle unix-type paths like /home/....
 # therefore we translate TEST_SRC_DIR to windows-path.
 if (CYGWIN)
   execute_process (COMMAND cygpath.exe -m ${CMAKE_CURRENT_SOURCE_DIR}
diff --git a/bazel/glog.bzl b/bazel/glog.bzl
index 40833b461..69c4517bc 100644
--- a/bazel/glog.bzl
+++ b/bazel/glog.bzl
@@ -187,6 +187,7 @@ def glog_library(namespace = "google", with_gflags = 1, **kwargs):
     )
 
     common_config = {
+        "@ac_cv_cxx11_atomic@": "1",
         "@ac_cv_cxx11_nullptr_t@": "1",
         "@ac_cv_cxx_using_operator@": "1",
         "@ac_cv_have_inttypes_h@": "0",
diff --git a/src/glog/logging.h.in b/src/glog/logging.h.in
index a9b0d461d..bb7c3f8b5 100644
--- a/src/glog/logging.h.in
+++ b/src/glog/logging.h.in
@@ -99,7 +99,7 @@
 #include <gflags/gflags.h>
 #endif
 
-#ifdef HAVE_CXX11_ATOMIC
+#if @ac_cv_have_cxx11_atomic@
 #include <atomic>
 #elif defined(OS_WINDOWS)
 #include <Windows.h>