Wed Apr 16 16:55:36 1997 Marcus G. Daniels <marcus@cathcart.sysc.pdx.edu>

	* configure.in: Replace AC_PROG_CC with AC_PROG_CC_LOCAL.
	If cross compiling do Lex/Yacc checks with BUILD_CC.
        Check CC and BUILD_CC for libraries having the needed support,
	and substitute discovery in installed_clib.

	* aclocal.m4: New file.  These replacement macros are to handle
	the case where there is a cross compiler but no supporting files.

	* Makefile.in (installed-clib): Don't hardwire a Hurd libcrt.a.
	(cross_linkable): Only define cross-migcom variable when it will
	be possible to build it.
	(all, install): Use $(cross-migcom).
	(install): Install cross-migcom only if was to be built.
	(mkinstalldirs): Add $(bindir), $(includedir)/mach/exec
	(cross-lexxer.o lexxer.o): lexxer.o needs cpu.h.
	(./cross-migcom): Prevent dependency generation for cross-* MiG files
	unless they can actually be built.

1 files changed, 73 insertions, 0 deletions

diff --git a/aclocal.m4 b/aclocal.m4
new file mode 100644
index 00000000..3d04b825
--- /dev/null
+++ b/aclocal.m4
@@ -0,0 +1,73 @@
+dnl These modifications are to allow for an empty cross compiler tree.
+dnl In the situation that cross-linking is impossible, the variable
+dnl `cross_linkable' will be substituted with "yes".
+
+dnl
+AC_DEFUN(AC_PROG_CC_LOCAL,
+[AC_BEFORE([$0], [AC_PROG_CPP])dnl
+AC_CHECK_PROG(CC, gcc, gcc)
+if test -z "$CC"; then
+  AC_CHECK_PROG(CC, cc, cc, , , /usr/ucb/cc)
+  test -z "$CC" && AC_MSG_ERROR([no acceptable cc found in \$PATH])
+fi
+
+AC_PROG_CC_WORKS_LOCAL
+AC_PROG_CC_GNU
+
+if test $ac_cv_prog_gcc = yes; then
+  GCC=yes
+dnl Check whether -g works, even if CFLAGS is set, in case the package
+dnl plays around with CFLAGS (such as to build both debugging and
+dnl normal versions of a library), tasteless as that idea is.
+  ac_test_CFLAGS="${CFLAGS+set}"
+  ac_save_CFLAGS="$CFLAGS"
+  CFLAGS=
+dnl  AC_PROG_CC_G
+  if test "$ac_test_CFLAGS" = set; then
+    CFLAGS="$ac_save_CFLAGS"
+dnl # This doesn't work on Linux (libc-4.5.26): Because of differences between
+dnl # the shared and the static libraries there are less symbols available
+dnl # without -g than with -g. It is therefore better to run the configuration
+dnl # without -g and to add -g afterwards than the contrary. So don't add
+dnl # -g to the CFLAGS now.
+dnl  elif test $ac_cv_prog_cc_g = yes; then
+dnl    CFLAGS="-g -O"
+  else
+dnl    CFLAGS="-O"
+    # Add "-O" to both the CC and CPP commands, to eliminate possible confusion
+    # that results from __OPTIMIZE__ being defined for CC but not CPP.
+changequote(, )dnl
+    if echo "$CC " | grep ' -O[1-9 ]' > /dev/null 2>&1; then
+changequote([, ])dnl
+      : # already optimizing
+    else
+      CC="$CC -O"
+      ac_cv_prog_CC="$CC"
+    fi
+  fi
+else
+  GCC=
+dnl # See above.
+dnl   test "${CFLAGS+set}" = set || CFLAGS="-g"
+fi
+])
+
+AC_DEFUN(AC_PROG_CC_WORKS_LOCAL,
+[AC_MSG_CHECKING([whether the C compiler ($CC $CFLAGS $LDFLAGS) works])
+AC_LANG_SAVE
+AC_LANG_C
+AC_TRY_COMPILER([main(){return(0);}], ac_cv_prog_cc_works, ac_cv_prog_cc_cross)
+AC_LANG_RESTORE
+AC_MSG_RESULT($ac_cv_prog_cc_works)
+if test $ac_cv_prog_cc_works = no; then
+ cross_linkable=no
+ ac_cv_prog_cc_cross=yes
+ # AC_MSG_ERROR([installation or configuration problem: C compiler cannot create executables.])
+else
+ cross_linkable=yes
+fi
+AC_MSG_CHECKING([whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler])
+AC_MSG_RESULT($ac_cv_prog_cc_cross)
+AC_SUBST(cross_linkable)
+cross_compiling=$ac_cv_prog_cc_cross
+])