查看编译器的默认include路径

在shell下运行：

$ echo | gcc -v -x c++ -E -

或者

$ echo | g++ -v -x c++ -E -

 

可以看到类似如下的结果

Using built-in specs.
Target: x86_64-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-libgcj-multifile --enable-languages=c,c++,objc,obj-c++,java,fortran,ada --enable-java-awt=gtk --disable-dssi --disable-plugin --with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre --with-cpu=generic --host=x86_64-redhat-linux
Thread model: posix
gcc version 4.1.2 20080704 (Red Hat 4.1.2-50)
 /usr/libexec/gcc/x86_64-redhat-linux/4.1.2/cc1plus -E -quiet -v -D_GNU_SOURCE - -mtune=generic
ignoring nonexistent directory "/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../x86_64-redhat-linux/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2
 /usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2/x86_64-redhat-linux
 /usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2/backward
 /usr/local/include
 /usr/lib/gcc/x86_64-redhat-linux/4.1.2/include
 /usr/include
End of search list.