Macro: ac_prog_cc_for_build

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# ac_prog_cc_for_build

## Synopsis

`AC_PROG_CC_FOR_BUILD`

## Version

1.1.1.1 (2001/07/26) Cross_Compilation @ ac-archive-0.5.32

## Author

Paolo Bonzini <bonzini@gnu.org>

## Description

This macro searches for a C compiler that generates native executables, that is a C compiler that surely is not a cross-compiler. This can be useful if you have to generate source code at compile-time like for example GCC does.

The macro sets the CC_FOR_BUILD and CPP_FOR_BUILD macros to anything needed to compile or link (CC_FOR_BUILD) and preprocess (CPP_FOR_BUILD). The value of these variables can be overridden by the user by specifying a compiler with an environment variable (like you do for standard CC).

It also sets BUILD_EXEEXT and BUILD_OBJEXT to the executable and object file extensions for the build platform, and GCC_FOR_BUILD to `yes' if the compiler we found is GCC. All these variables but GCC_FOR_BUILD are substituted in the Makefile.

## M4 Source Code

    AC_DEFUN([AC_PROG_CC_FOR_BUILD], [dnl
    AC_REQUIRE([AC_PROG_CC])dnl
    AC_REQUIRE([AC_PROG_CPP])dnl
    AC_REQUIRE([AC_EXEEXT])dnl
    AC_REQUIRE([AC_CANONICAL_SYSTEM])dnl
    dnl
    pushdef([AC_TRY_COMPILER], [
    cat > conftest.$ac_ext << EOF
    #line __oline__ "configure"
    #include "confdefs.h"
    [$1]
    EOF
    # If we can't run a trivial program, we are probably using a cross
    compiler.
    # Fail miserably.
    if AC_TRY_EVAL(ac_link) && test -s conftest${ac_exeext} && (./conftest;
    exit) 2>/dev/null; then
      [$2]=yes
    else
      echo "configure: failed program was:" >&AC_FD_CC
      cat conftest.$ac_ext >&AC_FD_CC
      [$2]=no
    fi
    [$3]=no
    rm -fr conftest*])dnl

    dnl Use the standard macros, but make them use other variable names
    dnl
    pushdef([cross_compiling], [#])dnl
    pushdef([ac_cv_prog_CPP], ac_cv_build_prog_CPP)dnl
    pushdef([ac_cv_prog_gcc], ac_cv_build_prog_gcc)dnl
    pushdef([ac_cv_prog_cc_works], ac_cv_build_prog_cc_works)dnl
    pushdef([ac_cv_prog_cc_cross], ac_cv_build_prog_cc_cross)dnl
    pushdef([ac_cv_prog_cc_g], ac_cv_build_prog_cc_g)dnl
    pushdef([ac_cv_exeext], ac_cv_build_exeext)dnl
    pushdef([ac_cv_objext], ac_cv_build_objext)dnl
    pushdef([ac_exeext], ac_build_exeext)dnl
    pushdef([ac_objext], ac_build_objext)dnl
    pushdef([CC], CC_FOR_BUILD)dnl
    pushdef([CPP], CPP_FOR_BUILD)dnl
    pushdef([CFLAGS], CFLAGS_FOR_BUILD)dnl
    pushdef([CPPFLAGS], CPPFLAGS_FOR_BUILD)dnl
    pushdef([host], build)dnl
    pushdef([host_alias], build_alias)dnl
    pushdef([host_cpu], build_cpu)dnl
    pushdef([host_vendor], build_vendor)dnl
    pushdef([host_os], build_os)dnl
    pushdef([ac_cv_host], ac_cv_build)dnl
    pushdef([ac_cv_host_alias], ac_cv_build_alias)dnl
    pushdef([ac_cv_host_cpu], ac_cv_build_cpu)dnl
    pushdef([ac_cv_host_vendor], ac_cv_build_vendor)dnl
    pushdef([ac_cv_host_os], ac_cv_build_os)dnl
    pushdef([ac_cpp], ac_build_cpp)dnl
    pushdef([ac_compile], ac_build_compile)dnl
    pushdef([ac_link], ac_build_link)dnl

    dnl Defeat the anti-duplication mechanism
    dnl
    undefine([AC_PROVIDE_AC_PROG_CPP])dnl
    undefine([AC_PROVIDE_AC_PROG_C])dnl
    undefine([AC_PROVIDE_AC_EXEEXT])dnl

    AC_PROG_CC
    AC_PROG_CPP
    AC_EXEEXT

    dnl Restore the old definitions
    dnl
    popdef([AC_TRY_COMPILER])dnl
    popdef([ac_link])dnl
    popdef([ac_compile])dnl
    popdef([ac_cpp])dnl
    popdef([ac_cv_host_os])dnl
    popdef([ac_cv_host_vendor])dnl
    popdef([ac_cv_host_cpu])dnl
    popdef([ac_cv_host_alias])dnl
    popdef([ac_cv_host])dnl
    popdef([host_os])dnl
    popdef([host_vendor])dnl
    popdef([host_cpu])dnl
    popdef([host_alias])dnl
    popdef([host])dnl
    popdef([CPPFLAGS])dnl
    popdef([CFLAGS])dnl
    popdef([CPP])dnl
    popdef([CC])dnl
    popdef([ac_objext])dnl
    popdef([ac_exeext])dnl
    popdef([ac_cv_objext])dnl
    popdef([ac_cv_exeext])dnl
    popdef([ac_cv_prog_cc_g])dnl
    popdef([ac_cv_prog_cc_works])dnl
    popdef([ac_cv_prog_cc_cross])dnl
    popdef([ac_cv_prog_gcc])dnl
    popdef([ac_cv_prog_cc])dnl
    popdef([cross_compiling])dnl

    dnl Finally, set Makefile variables
    dnl
    BUILD_EXEEXT=$ac_build_exeext
    BUILD_OBJEXT=$ac_build_objext
    AC_SUBST(BUILD_EXEEXT)dnl
    AC_SUBST(BUILD_OBJEXT)dnl
    AC_SUBST([CFLAGS_FOR_BUILD])dnl
    AC_SUBST([CPPFLAGS_FOR_BUILD])dnl
    ])