2013-07-17 32 views
5

當我嘗試使用原子方法is_lock_free()時,出現以下編譯錯誤。mingw-4.8.1原子問題

struct Simple1 { int i; }; 
struct Simple2 { int a; int b; }; 
struct Simple3 { int a; int b; int c; }; 

int main() 
{ 
    atomic<Counter> counter; 
    atomic<Param> param; 
    atomic<Simple1> s1; 
    atomic<Simple2> s2; 
    atomic<Simple3> s3; 

    cout 
     << "Is s1 lock free? " << boolalpha << s1.is_lock_free() << '\n' 
     << "Is s2 lock free? " << boolalpha << s2.is_lock_free() << '\n' 
     << "Is s3 lock free? " << boolalpha << s3.is_lock_free() << '\n'; 
    } 

s1.is_lock_free() and s2.is_lock_free()都還好和atomic<builtin>::is_lock_free(),其中builtin是fondamental型,效果很好。

但對於S3的is_lock_free通話給出了一個鏈接錯誤:undefined reference to __atomic_is_lock_free

我是否需要鏈接一些外部庫?我能做什麼?

編輯1

同樣的問題發生在gcc4.8.1在Ubuntu 13.04

的COMAND行選項是:

g++ -O0 -g3 -Wall -c -fmessage-length=0 -std=c++11 -o "atomic_test.o" "atomic_test.cpp" 
g++ -std=c++11 -o hello.exe atomic_test.o 

編輯2

我在gcc上添加了-latomic和-lpthread,但是我有同樣的錯誤:

04:09:37: Running steps for project atomic... 
04:09:37: Configuration unchanged, skipping qmake step. 
04:09:37: Starting: "/usr/bin/make" 
/home/dmdtek/Qt/5.1.0/gcc_64/bin/qmake -spec linux-g++ CONFIG+=debug  CONFIG+=declarative_debug CONFIG+=qml_debug -o Makefile ../atomic/atomic.pro 
g++ -latomic -lpthread -Wl,-rpath,/home/dmdtek/Qt/5.1.0/gcc_64 -o atomic main.o  
main.o: In function `std::atomic<Simple3>::is_lock_free() const': 
/usr/include/c++/4.8/atomic:191: undefined reference to `__atomic_is_lock_free' 
main.o: In function `std::atomic<long double>::is_lock_free() const': 
/usr/include/c++/4.8/atomic:191: undefined reference to `__atomic_is_lock_free' 
collect2: error: ld returned 1 exit status 
make: *** [atomic] Error 1 
04:09:37: The process "/usr/bin/make" exited with code 2. 
Error while building/deploying project atomic (kit: Desktop Qt 5.1.0 GCC 64bit) 
When executing step 'Make' 
04:09:37: Elapsed time: 00:00. 

libatomic存在我的系統上:

$ ldconfig -v | grep atomic 
/sbin/ldconfig.real: Path `/lib/x86_64-linux-gnu' given more than once 
/sbin/ldconfig.real: Path `/usr/lib/x86_64-linux-gnu' given more than once 
libatomic.so.1 -> libatomic.so.1.0.0 
/sbin/ldconfig.real: Can't create temporary cache file /etc/ld.so.cache~: Permission denied 

回答

7

您需要libatomic鏈接(通過GCC提供):

g++ -std=c++11 -o hello.exe atomic_test.o -latomic 
+0

仍然無法正常工作 –

+1

可能我的錯:嘗試在命令行中的'.o'之前移動'-latomic'並讓我知道它是否有效,以便我可以更新我的答案。 – syam

+0

沒有相同的結果:'g ++ -c -pipe -std = C++ 11 -lpthread -g -Wall -W -fPIE -DQT_QML_DEBUG -DQT_DECLARATIVE_DEBUG -I ../../../../ Qt/5.1。 0/gcc_64/mkspecs/linux-g ++ -I ../attr -I。 -o main.o ../atc/main.cpp''g ++ -latomic -lpthread -Wl,-rpath,/ home/dmdtek/Qt/5.1.0/gcc_64 -o atomic main.o' –