From 80a0e27d8cd34b3566b5b3eda8ea6fce9dc77f75 Mon Sep 17 00:00:00 2001
From: Dw9 <xweimvp@gmail.com>
Date: Sat, 29 Jan 2022 22:40:08 +0800
Subject: [PATCH] link atomic library automatic when compile on raspberrypi 
 (#1405)
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* 增加检测atomic源文件

* 支持树莓派编译，自动检测atomic链接库

* 精简cmake操作
---
 CMakeLists.txt                | 12 ++++++++++++
 cmake/checks/atomic_check.cpp | 12 ++++++++++++
 2 files changed, 24 insertions(+)
 create mode 100644 cmake/checks/atomic_check.cpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 83479245..c4cc97e7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -25,6 +25,18 @@ if (CMAKE_SYSTEM_NAME MATCHES "Linux")
     SET(LIBRARY_OUTPUT_PATH ${RELEASE_DIR}/linux/${CMAKE_BUILD_TYPE})
     SET(EXECUTABLE_OUTPUT_PATH ${RELEASE_DIR}/linux/${CMAKE_BUILD_TYPE})
     add_compile_options(-fPIC -Wall -Wno-unused-variable -Wno-unused-value)
+    INCLUDE(CheckCXXSourceCompiles)
+    file(READ ${CMAKE_CURRENT_SOURCE_DIR}/cmake/checks/atomic_check.cpp atomic_check_cpp)
+    CHECK_CXX_SOURCE_COMPILES("${atomic_check_cpp}" HAVE_CXX_ATOMICS_WITHOUT_LIB)
+    if(NOT HAVE_CXX_ATOMICS_WITHOUT_LIB)
+        list(APPEND CMAKE_REQUIRED_LIBRARIES "atomic")
+        CHECK_CXX_SOURCE_COMPILES("${atomic_check_cpp}" HAVE_CXX_ATOMICS_WITH_LIB)
+        if(NOT HAVE_CXX_ATOMICS_WITH_LIB)
+            message(WARNING "Compiler doesn't support std::atomic<long long>")
+        else()
+            set(CMAKE_CXX_LINK_FLAGS "${CMAKE_CXX_LINK_FLAGS} -latomic")
+        endif()
+    endif()
 elseif (CMAKE_SYSTEM_NAME MATCHES "Windows")
     if (CMAKE_CL_64)
         set(CL_32_64 64)
diff --git a/cmake/checks/atomic_check.cpp b/cmake/checks/atomic_check.cpp
new file mode 100644
index 00000000..f25e2d9f
--- /dev/null
+++ b/cmake/checks/atomic_check.cpp
@@ -0,0 +1,12 @@
+#include <atomic>
+
+static int test()
+{
+    std::atomic<long long> x;
+    return x;
+}
+
+int main()
+{
+    return test();
+}
\ No newline at end of file