Patch adapted from Nix.
Upstream-status: Submitted to bug-bc@gnu.org.
diff --git a/bc/Makefile.am b/bc/Makefile.am
index d9d412e..13f2b1e 100644
--- a/bc/Makefile.am
+++ b/bc/Makefile.am
@@ -8,7 +8,7 @@ EXTRA_DIST = bc.h bcdefs.h const.h fix-libmath_h global.h libmath.b proto.h \
sbc.y
noinst_HEADERS = libmath.h
-DISTCLEANFILES = sbc sbc.c sbc.h libmath.h
+DISTCLEANFILES = fbc sbc sbc.c sbc.h libmath.h
MAINTAINERCLEANFILES = Makefile.in bc.c bc.h scan.c \
bc.y bcdefs.h const.h execute.c fix-libmath_h \
@@ -17,6 +17,7 @@ MAINTAINERCLEANFILES = Makefile.in bc.c bc.h scan.c \
AM_CPPFLAGS = -I$(srcdir) -I$(srcdir)/../h
LIBBC = ../lib/libbc.a
+LIBBC_HOST = ../lib/libbc_host.a
LIBL = @LEXLIB@
LDADD = $(LIBBC) $(LIBL) @READLINELIB@
@@ -29,15 +30,22 @@ $(PROGRAMS): libmath.h $(LIBBC)
scan.o: bc.h
global.o: libmath.h
-fbcOBJ = main.o bc.o scan.o execute.o load.o storage.o util.o warranty.o
+%.o_host: CC := $(CC_FOR_BUILD)
+%.o_host: %.c
+ $(COMPILE) -c -o $@ $<
-libmath.h: libmath.b $(fbcOBJ) $(LIBBC)
- echo '{0}' > libmath.h
- $(MAKE) global.o
- $(LINK) -o fbc $(fbcOBJ) global.o $(LIBBC) $(LIBL) $(READLINELIB) $(LIBS)
- ./fbc -c $(srcdir)/libmath.b </dev/null >libmath.h
+fbcOBJ = $(addsuffix _host,\
+ main.o bc.o scan.o execute.o load.o storage.o util.o warranty.o)
+
+global_host.c: global.c
+ sed 's/#include "libmath.h"/{0}/' $< > $@
+
+fbc: $(fbcOBJ) global_host.o_host $(LIBBC_HOST) $(LIBS)
+ $(CC_FOR_BUILD) $(LIBL) $(READLINELIB) -o $@ $^
+
+libmath.h: libmath.b fbc $(LIBBC_HOST)
+ ./fbc -c $(srcdir)/libmath.b < /dev/null > libmath.h
$(srcdir)/fix-libmath_h
- rm -f ./fbc ./global.o
sbcOBJ = main.o sbc.o scan.o execute.o global.o load.o storage.o util.o \
warranty.o
diff --git a/configure.ac b/configure.ac
index fc74573..5cabb73 100644
--- a/configure.ac
+++ b/configure.ac
@@ -20,6 +20,7 @@ m4_define([dc_version], 1.4.1)
AC_INIT([bc],[bc_version])
AC_CONFIG_SRCDIR(doc/bc.1)
+AC_CONFIG_MACRO_DIR([m4])
AM_INIT_AUTOMAKE([dist-bzip2])
AC_CONFIG_HEADERS(config.h)
@@ -35,6 +36,7 @@ AC_DEFINE([DC_COPYRIGHT],
[Define the dc copyright line.])
AC_PROG_CC
+AX_CC_FOR_BUILD
AC_USE_SYSTEM_EXTENSIONS
AM_PROG_LEX
diff --git a/lib/Makefile.am b/lib/Makefile.am
index ec4bf59..24c9f42 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -1,5 +1,5 @@
## Process this file with automake to produce Makefile.in
-noinst_LIBRARIES = libbc.a
+noinst_LIBRARIES = libbc.a libbc_host.a
AM_CPPFLAGS = -I. -I.. -I$(srcdir)/../h
@@ -7,8 +7,6 @@ libbc_a_SOURCES = getopt.c getopt1.c vfprintf.c number.c
DEFS = @DEFS@ $(DEFSADD)
-AM_CFLAGS = @CFLAGS@
-
MAINTAINERCLEANFILES = Makefile.in number.c
CLEANFILES = testmul specialnumber muldigits.h
@@ -24,3 +22,11 @@ testmul: testmul.o number.o
specialnumber: newnumber.o
cp newnumber.o number.o
+
+%.o_host: CC := $(CC_FOR_BUILD)
+%.o_host : %.c
+ $(COMPILE) -c -o $@ $<
+
+libbc_host.a : $(addsuffix _host,$(libbc_a_OBJECTS))
+ ar cru $@ $+
+ ranlib $@
diff --git a/m4/cc_for_build.m4 b/m4/cc_for_build.m4
new file mode 100644
index 0000000..c62ffad
--- /dev/null
+++ b/m4/cc_for_build.m4
@@ -0,0 +1,77 @@
+# ===========================================================================
+# https://www.gnu.org/software/autoconf-archive/ax_cc_for_build.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+# AX_CC_FOR_BUILD
+#
+# DESCRIPTION
+#
+# Find a build-time compiler. Sets CC_FOR_BUILD and EXEEXT_FOR_BUILD.
+#
+# LICENSE
+#
+# Copyright (c) 2010 Reuben Thomas <rrt@sc3d.org>
+# Copyright (c) 1999 Richard Henderson <rth@redhat.com>
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the
+# Free Software Foundation, either version 3 of the License, or (at your
+# option) any later version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+# Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program. If not, see <https://www.gnu.org/licenses/>.
+#
+# As a special exception, the respective Autoconf Macro's copyright owner
+# gives unlimited permission to copy, distribute and modify the configure
+# scripts that are the output of Autoconf when processing the Macro. You
+# need not follow the terms of the GNU General Public License when using
+# or distributing such scripts, even though portions of the text of the
+# Macro appear in them. The GNU General Public License (GPL) does govern
+# all other use of the material that constitutes the Autoconf Macro.
+#
+# This special exception to the GPL applies to versions of the Autoconf
+# Macro released by the Autoconf Archive. When you make and distribute a
+# modified version of the Autoconf Macro, you may extend this special
+# exception to the GPL to apply to your modified version as well.
+
+#serial 3
+
+dnl Get a default for CC_FOR_BUILD to put into Makefile.
+AC_DEFUN([AX_CC_FOR_BUILD],
+[# Put a plausible default for CC_FOR_BUILD in Makefile.
+if test -z "$CC_FOR_BUILD"; then
+ if test "x$cross_compiling" = "xno"; then
+ CC_FOR_BUILD='$(CC)'
+ else
+ CC_FOR_BUILD=gcc
+ fi
+fi
+AC_SUBST(CC_FOR_BUILD)
+# Also set EXEEXT_FOR_BUILD.
+if test "x$cross_compiling" = "xno"; then
+ EXEEXT_FOR_BUILD='$(EXEEXT)'
+else
+ AC_CACHE_CHECK([for build system executable suffix], bfd_cv_build_exeext,
+ [rm -f conftest*
+ echo 'int main () { return 0; }' > conftest.c
+ bfd_cv_build_exeext=
+ ${CC_FOR_BUILD} -o conftest conftest.c 1>&5 2>&5
+ for file in conftest.*; do
+ case $file in
+ *.c | *.o | *.obj | *.ilk | *.pdb) ;;
+ *) bfd_cv_build_exeext=`echo $file | sed -e s/conftest//` ;;
+ esac
+ done
+ rm -f conftest*
+ test x"${bfd_cv_build_exeext}" = x && bfd_cv_build_exeext=no])
+ EXEEXT_FOR_BUILD=""
+ test x"${bfd_cv_build_exeext}" != xno && EXEEXT_FOR_BUILD=${bfd_cv_build_exeext}
+fi
+AC_SUBST(EXEEXT_FOR_BUILD)])dnl
