我使用Cygwin下的crosstool脚本构建了以下针对Sparc架构的编译器:gcc-4.1.1和4.2.0 20061024(预发布版)。
$ ./sparc-unknown-linux-gnu-gcc -v
Using built-in specs.
Target: sparc-unknown-linux-gnu
Configured with: /crosstool-0.43/build/sparc-unknown-linux-gnu/gcc-4.1.1-glibc-2.3.6/gcc-4.1.1/configure --target=sparc-unknown-linux-gnu --host=i686-host_pc-cygwin --prefix=/opt/crosstool/gcc-4.1.1-glibc-2.3.6/sparc-unknown-linux-gnu --with-headers=/opt/crosstool/gcc-4.1.1-glibc-2.3.6/sparc-unknown-linux-gnu/sparc-unknown-linux-gnu/include --with-local-prefix=/opt/crosstool/gcc-4.1.1-glibc-2.3.6/sparc-unknown-linux-gnu/sparc-unknown-linux-gnu --disable-nls --enable-threads=posix --enable-symvers=gnu --enable-__cxa_atexit --enable-languages=c,c++ --enable-shared --enable-c99 --enable-long-long
Thread model: posix
gcc version 4.1.1
并且
$ ./sparc-unknown-linux-gnu-gcc -v
Using built-in specs.
Target: sparc-unknown-linux-gnu
Configured with: /crosstool-0.43/build/sparc-unknown-linux-gnu/gcc-4.2-20061024- glibc-2.3.6/gcc-4.2-20061024/configure --target=sparc-unknown-linux-gnu --host=i 686-host_pc-cygwin --prefix=/opt/crosstool/gcc-4.2-20061024-glibc-2.3.6/sparc-un known-linux-gnu --with-headers=/opt/crosstool/gcc-4.2-20061024-glibc-2.3.6/sparc -unknown-linux-gnu/sparc-unknown-linux-gnu/include --with-local-prefix=/opt/cros stool/gcc-4.2-20061024-glibc-2.3.6/sparc-unknown-linux-gnu/sparc-unknown-linux-g nu --disable-nls --enable-threads=posix --enable-symvers=gnu --enable-__cxa_atex it --enable-languages=c,c++ --enable-shared --enable-c99 --enable-long-long
Thread model: posix
gcc version 4.2.0 20061024 (prerelease)
我需要在我的程序中使用与原子内建函数相关的__sync_val_compare_and_swap
函数,该函数支持gcc 4.1.*版本。为此,我尝试编译简单的C代码:
long cmpxchg( long* value, long comp_val, long new_val )
{
return __sync_val_compare_and_swap( value, comp_val, new_val );
}
int main()
{
return 0;
}
但我遇到了以下错误:(在两个编译器上都出现):
$ ./sparc-unknown-linux-gnu-gcc test_cas.c -o test_cas
/tmp/ccREXHsP.o: In function `cmpxchg':
test_cas.c:(.text+0x24): undefined reference to `__sync_val_compare_and_swap_4'
collect2: ld returned 1 exit status
什么问题?也许是我错误地构建编译器?也许Sparc架构(SPARC v8)不支持此功能?我尝试编译我的另一个程序 - 一切都很好(已编译并执行)。
./sparc-unknown-linux-gnu-gcc test_cas.c -o test_cas -lgcc_s
。 - Coren/usr/lib
中运行nm
或objdump
并搜索该函数,这个方案怎么样? - John Zwinck