所以,今天我正在编写一些单元测试,突然G++给了我一个关于GNU C和我的一个名为
major
. 为什么我不能有一个名为
这是一个最低可行的测试片段:
// Any of these includes trigger the warnings
#include <random>
#include <cstdlib>
class my_class {
public:
void major() const;
};
inline void my_class::major() const {}
int main(void) {
my_class my_obj;
my_obj.major();
return 0;
}
这是编译的输出(使用
g++ --std=c++14 -o test-gcc-major test-gcc-major.cpp
):
[flisboac@sonic ~]$ uname -a && lsb_release -a && g++ -v && g++ --std=c++14 -o test-gcc-major test-gcc-major.cpp && ./test-gcc-major
Linux sonic 4.12.10-1-ARCH #1 SMP PREEMPT Wed Aug 30 12:18:42 CEST 2017 x86_64 GNU/Linux
LSB Version: 1.4
Distributor ID: Arch
Description: Arch Linux
Release: rolling
Codename: n/a
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/7.1.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /build/gcc-multilib/src/gcc/configure --prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/ --enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++ --enable-shared --enable-threads=posix --enable-libmpx --with-system-zlib --with-isl --enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu --disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object --enable-linker-build-id --enable-lto --enable-plugin --enable-install-libiberty --with-linker-hash-style=gnu --enable-gnu-indirect-function --enable-multilib --disable-werror --enable-checking=release --enable-default-pie --enable-default-ssp
Thread model: posix
gcc version 7.1.1 20170630 (GCC)
test-gcc-major.cpp:7:13: warning: In the GNU C Library, "major" is defined
by <sys/sysmacros.h>. For historical compatibility, it is
currently defined by <sys/types.h> as well, but we plan to
remove this soon. To use "major", include <sys/sysmacros.h>
directly. If you did not intend to use a system-defined macro
"major", you should undefine it after including <sys/types.h>.
void major() const;
^~~~~~~~
test-gcc-major.cpp:10:13: warning: In the GNU C Library, "major" is defined
by <sys/sysmacros.h>. For historical compatibility, it is
currently defined by <sys/types.h> as well, but we plan to
remove this soon. To use "major", include <sys/sysmacros.h>
directly. If you did not intend to use a system-defined macro
"major", you should undefine it after including <sys/types.h>.
inline void my_class::major() const {}
^~~~~~~~~~~~~~~~~~~~~~~~~~
test-gcc-major.cpp:14:13: warning: In the GNU C Library, "major" is defined
by <sys/sysmacros.h>. For historical compatibility, it is
currently defined by <sys/types.h> as well, but we plan to
remove this soon. To use "major", include <sys/sysmacros.h>
directly. If you did not intend to use a system-defined macro
"major", you should undefine it after including <sys/types.h>.
my_obj.major();
那么,有人知道为什么会提出这个警告吗?我甚至没有在我的代码中使用C。我用的是
<random>
,这本身不是C(但可能包括一个“C”库,谁知道呢?)。
在任何情况下,是否有任何方法来检测需求和定义
在编译时(例如,使用一些预处理器voodoo)?
更新:
我正在使用
<
<cstdlib>
. 我刚发现
<cstdlib>
也会触发警告。