+
+# Test for GNAT.
+# We require the gnatbind program, and a compiler driver that
+# understands Ada. We use the user's CC setting, already found.
+#
+# Sets the shell variable have_gnat to yes or no as appropriate, and
+# substitutes GNATBIND.
+AC_DEFUN([ACX_PROG_GNAT],
+[AC_REQUIRE([AC_CHECK_TOOL_PREFIX])
+AC_REQUIRE([AC_PROG_CC])
+AC_CHECK_TOOL(GNATBIND, gnatbind, no)
+AC_CACHE_CHECK([whether compiler driver understands Ada],
+ acx_cv_cc_gcc_supports_ada,
+[cat >conftest.adb <<EOF
+procedure conftest is begin null; end conftest;
+EOF
+acx_cv_cc_gcc_supports_ada=no
+# There is a bug in old released versions of GCC which causes the
+# driver to exit successfully when the appropriate language module
+# has not been installed. This is fixed in 2.95.4, 3.0.2, and 3.1.
+# Therefore we must check for the error message as well as an
+# unsuccessful exit.
+# Other compilers, like HP Tru64 UNIX cc, exit successfully when
+# given a .adb file, but produce no object file. So we must check
+# if an object file was really produced to guard against this.
+errors=`(${CC} -c conftest.adb) 2>&1 || echo failure`
+if test x"$errors" = x && test -f conftest.$ac_objext; then
+ acx_cv_cc_gcc_supports_ada=yes
+fi
+rm -f conftest.*])
+
+if test x$GNATBIND != xno && test x$acx_cv_cc_gcc_supports_ada != xno; then
+ have_gnat=yes
+else
+ have_gnat=no
+fi
+])
+
+dnl 'make compare' can be significantly faster, if cmp itself can
+dnl skip bytes instead of using tail. The test being performed is
+dnl "if cmp --ignore-initial=2 t1 t2 && ! cmp --ignore-initial=1 t1 t2"
+dnl but we need to sink errors and handle broken shells. We also test
+dnl for the parameter format "cmp file1 file2 skip1 skip2" which is
+dnl accepted by cmp on some systems.
+AC_DEFUN([ACX_PROG_CMP_IGNORE_INITIAL],
+[AC_CACHE_CHECK([how to compare bootstrapped objects], gcc_cv_prog_cmp_skip,
+[ echo abfoo >t1
+ echo cdfoo >t2
+ gcc_cv_prog_cmp_skip='tail +16c $$f1 > tmp-foo1; tail +16c $$f2 > tmp-foo2; cmp tmp-foo1 tmp-foo2'
+ if cmp t1 t2 2 2 > /dev/null 2>&1; then
+ if cmp t1 t2 1 1 > /dev/null 2>&1; then
+ :
+ else
+ gcc_cv_prog_cmp_skip='cmp $$f1 $$f2 16 16'
+ fi
+ fi
+ if cmp --ignore-initial=2 t1 t2 > /dev/null 2>&1; then
+ if cmp --ignore-initial=1 t1 t2 > /dev/null 2>&1; then
+ :
+ else
+ gcc_cv_prog_cmp_skip='cmp --ignore-initial=16 $$f1 $$f2'
+ fi
+ fi
+ rm t1 t2
+])
+do_compare="$gcc_cv_prog_cmp_skip"
+AC_SUBST(do_compare)
+])
+
+dnl See whether we can include both string.h and strings.h.
+AC_DEFUN([ACX_HEADER_STRING],
+[AC_CACHE_CHECK([whether string.h and strings.h may both be included],
+ gcc_cv_header_string,
+[AC_TRY_COMPILE([#include <string.h>
+#include <strings.h>], , gcc_cv_header_string=yes, gcc_cv_header_string=no)])
+if test $gcc_cv_header_string = yes; then
+ AC_DEFINE(STRING_WITH_STRINGS, 1, [Define if you can safely include both <string.h> and <strings.h>.])
+fi
+])
+
+dnl See if stdbool.h properly defines bool and true/false.
+dnl Check whether _Bool is built-in.
+AC_DEFUN([ACX_HEADER_STDBOOL],
+[AC_CACHE_CHECK([for working stdbool.h],
+ ac_cv_header_stdbool_h,
+[AC_TRY_COMPILE([#include <stdbool.h>],
+[bool foo = false;],
+ac_cv_header_stdbool_h=yes, ac_cv_header_stdbool_h=no)])
+if test $ac_cv_header_stdbool_h = yes; then
+ AC_DEFINE(HAVE_STDBOOL_H, 1,
+ [Define if you have a working <stdbool.h> header file.])
+fi
+AC_CACHE_CHECK(for built-in _Bool, gcc_cv_c__bool,
+[AC_TRY_COMPILE(,
+[_Bool foo;],
+gcc_cv_c__bool=yes, gcc_cv_c__bool=no)
+])
+if test $gcc_cv_c__bool = yes; then
+ AC_DEFINE(HAVE__BOOL, 1, [Define if the \`_Bool' type is built-in.])
+fi
+])
+
+dnl See if hard links work and if not, try to substitute $1 or simple copy.
+AC_DEFUN([ACX_PROG_LN],
+[AC_MSG_CHECKING(whether ln works)
+AC_CACHE_VAL(acx_cv_prog_LN,
+[rm -f conftestdata_t
+echo >conftestdata_f
+if ln conftestdata_f conftestdata_t 2>/dev/null
+then
+ acx_cv_prog_LN=ln
+else
+ acx_cv_prog_LN=no
+fi
+rm -f conftestdata_f conftestdata_t
+])dnl
+if test $acx_cv_prog_LN = no; then
+ LN="ifelse([$1],,cp,[$1])"
+ AC_MSG_RESULT([no, using $LN])
+else
+ LN="$acx_cv_prog_LN"
+ AC_MSG_RESULT(yes)
+fi
+AC_SUBST(LN)dnl
+])
+
+dnl GCC_TARGET_TOOL(PROGRAM, TARGET-VAR, HOST-VAR, IN-TREE-TOOL, LANGUAGE)
+AC_DEFUN([GCC_TARGET_TOOL],
+[AC_MSG_CHECKING(where to find the target $1)
+if test "x${build}" != "x${host}" ; then
+ if expr "x[$]$2" : "x/" > /dev/null; then
+ # We already found the complete path
+ AC_MSG_RESULT(pre-installed in `dirname [$]$2`)
+ else
+ # Canadian cross, just use what we found
+ AC_MSG_RESULT(pre-installed)
+ fi
+else
+ ifelse([$4],,,
+ [ok=yes
+ case " ${configdirs} " in
+ *" patsubst([$4], [/.*], []) "*) ;;
+ *) ok=no ;;
+ esac
+ ifelse([$5],,,
+ [case ,${enable_languages}, in
+ *,$5,*) ;;
+ *) ok=no ;;
+ esac])
+ if test $ok = yes; then
+ # An in-tree tool is available and we can use it
+ $2='$$r/$(HOST_SUBDIR)/$4'
+ AC_MSG_RESULT(just compiled)
+ el])if expr "x[$]$2" : "x/" > /dev/null; then
+ # We already found the complete path
+ AC_MSG_RESULT(pre-installed in `dirname [$]$2`)
+ elif test "x$target" = "x$host"; then
+ # We can use an host tool
+ $2='$($3)'
+ AC_MSG_RESULT(host tool)
+ else
+ # We need a cross tool
+ AC_MSG_RESULT(pre-installed)
+ fi
+fi])