gcc: Fixed Headers
1
1 13.4 Fixed Header Files
1 =======================
1
1 GCC needs to install corrected versions of some system header files.
1 This is because most target systems have some header files that won't
1 work with GCC unless they are changed. Some have bugs, some are
1 incompatible with ISO C, and some depend on special features of other
1 compilers.
1
1 Installing GCC automatically creates and installs the fixed header
1 files, by running a program called 'fixincludes'. Normally, you don't
1 need to pay attention to this. But there are cases where it doesn't do
1 the right thing automatically.
1
1 * If you update the system's header files, such as by installing a
1 new system version, the fixed header files of GCC are not
1 automatically updated. They can be updated using the 'mkheaders'
1 script installed in 'LIBEXECDIR/gcc/TARGET/VERSION/install-tools/'.
1
1 * On some systems, header file directories contain machine-specific
1 symbolic links in certain places. This makes it possible to share
1 most of the header files among hosts running the same version of
1 the system on different machine models.
1
1 The programs that fix the header files do not understand this
1 special way of using symbolic links; therefore, the directory of
1 fixed header files is good only for the machine model used to build
1 it.
1
1 It is possible to make separate sets of fixed header files for the
1 different machine models, and arrange a structure of symbolic links
1 so as to use the proper set, but you'll have to do this by hand.
1