我在 macOS Catalina 上遇到了头文件的问题。我遇到了以下类似于命令行工具错误的问题：
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/resource.h:443:29: error: parameter name omitted
int getiopolicy_np(int, int) __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_2_0);
^~~
和 GCC 错误
/usr/local/Cellar/gcc@8/8.3.0/lib/gcc/8/gcc/x86_64-apple-darwin18/8.3.0/include-fixed/math.h:535:15: error: storage class specified for parameter 'nextafte'
extern double nextafter(double, double);
我查看了头文件和gcc，使用这个回答作为参考。该回答表明：
Regarding header locations, I have Apples headers in /Library/Developer/CommandLineTools/:
$ sudo find /Library -name stdio.h
/Library/Developer/CommandLineTools/usr/include/c++/v1/stdio.h
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/stdio.h
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/stdio.h
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Kernel.
当我运行相同的命令时，标题位置略有不同：/Library/Developer/CommandLineTools/usr/include/c++/v1/stdio.h
/Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/usr/include/sys/stdio.h
/Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/usr/include/stdio.h
/Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/Kernel.framework/Versions/A/Headers/sys/stdio.h
/Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk/usr/include/sys/stdio.h
/Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk/usr/include/stdio.h
/Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk/System/Library/Frameworks/Kernel.framework/Versions/A/Headers/sys/stdio.h
如您所见，SDK现在已经分为MACOSX10.14和10.15，与以往不同。另一个区别是头文件。根据参考答案，
if you install gcc via brew, it will add headers in /usr/local/:
$ sudo find /usr -name stdio.h
/usr/local/Cellar/gcc/8.2.0/include/c++/8.2.0/tr1/stdio.h
/usr/local/Cellar/gcc/8.2.0/lib/gcc/8/gcc/x86_64-apple-darwin17.7.0/8.2.0/include/ssp/stdio.h
/usr/local/Cellar/gcc/8.2.0/lib/gcc/8/gcc/x86_64-apple-darwin17.7.0/8.2.0/include-fixed/stdio.h
/usr/local/Cellar/gcc/8.1.0/include/c++/8.1.0/tr1/stdio.h
/usr/local/Cellar/gcc/8.1.0/lib/gcc/8/gcc/x86_64-apple-darwin17.5.0/8.1.0/include/ssp/stdio.h
/usr/local/Cellar/gcc/8.1.0/lib/gcc/8/gcc/x86_64-apple-darwin17.5.0/8.1.0/include-fixed/stdio.h
/usr/local/Cellar/gcc/7.3.0_1/include/c++/7.3.0/tr1/stdio.h
/usr/local/Cellar/gcc/7.3.0_1/lib/gcc/7/gcc/x86_64-apple-darwin17.3.0/7.3.0/include/ssp/stdio.h
/usr/local/Cellar/gcc@7/7.3.0/include/c++/7.3.0/tr1/stdio.h
/usr/local/Cellar/gcc@7/7.3.0/lib/gcc/7/gcc/x86_64-apple-darwin17.5.0/7.3.0/include/ssp/stdio.h
/usr/local/Cellar/gcc@7/7.3.0/lib/gcc/7/gcc/x86_64-apple-darwin17.5.0/7.3.0/include-fixed/stdio.h
/usr/local/include/c++/8.2.0/tr1/stdio.h
/usr/local/lib/gcc/8/gcc/x86_64-apple-darwin17.7.0/8.2.0/include/ssp/stdio.h
/usr/local/lib/gcc/8/gcc/x86_64-apple-darwin17.7.0/8.2.0/include-fixed/stdio.h
然而，当我运行以上命令时，我得到以下结果：/usr/local/Cellar/gcc@8/8.3.0/include/c++/8.3.0/tr1/stdio.h
/usr/local/Cellar/gcc@8/8.3.0/lib/gcc/8/gcc/x86_64-apple-darwin18/8.3.0/include/ssp/stdio.h
/usr/local/Cellar/gcc@8/8.3.0/lib/gcc/8/gcc/x86_64-apple-darwin18/8.3.0/include-fixed/stdio.h
其他的头文件在哪里？这些命令在 macOS Catalina 中应该返回什么？