gcc/doc/gccint/standard-header-file-directories.rst

   1 ..
   2   Copyright 1988-2022 Free Software Foundation, Inc.
   3   This is part of the GCC manual.
   4   For copying conditions, see the copyright.rst file.
   5
   6 .. _header-dirs:
   7
   8 Standard Header File Directories
   9 --------------------------------
  10
  11 ``GCC_INCLUDE_DIR`` means the same thing for native and cross.  It is
  12 where GCC stores its private include files, and also where GCC
  13 stores the fixed include files.  A cross compiled GCC runs
  14 ``fixincludes`` on the header files in :samp:`$(tooldir)/include`.
  15 (If the cross compilation header files need to be fixed, they must be
  16 installed before GCC is built.  If the cross compilation header files
  17 are already suitable for GCC, nothing special need be done).
  18
  19 ``GPLUSPLUS_INCLUDE_DIR`` means the same thing for native and cross.  It
  20 is where :command:`g++` looks first for header files.  The C++ library
  21 installs only target independent header files in that directory.
  22
  23 ``LOCAL_INCLUDE_DIR`` is used only by native compilers.  GCC
  24 doesn't install anything there.  It is normally
  25 :samp:`/usr/local/include`.  This is where local additions to a packaged
  26 system should place header files.
  27
  28 ``CROSS_INCLUDE_DIR`` is used only by cross compilers.  GCC
  29 doesn't install anything there.
  30
  31 ``TOOL_INCLUDE_DIR`` is used for both native and cross compilers.  It
  32 is the place for other packages to install header files that GCC will
  33 use.  For a cross-compiler, this is the equivalent of
  34 :samp:`/usr/include`.  When you build a cross-compiler,
  35 ``fixincludes`` processes any header files in this directory.