This patch by Peter Collingbourne adds a local variant of the
move-if-change script, called mvifdiff, so that libgo can be built
outside of the GCC tree. Bootstrapped on x86_64-unknown-linux-gnu.
Committed to mainline.
Ian
Index: libgo/Makefile.am
===================================================================
--- libgo/Makefile.am (revision 217944)
+++ libgo/Makefile.am (working copy)
@@ -1007,7 +1007,7 @@ s-version: Makefile
echo 'const theVersion = "'`$(GOC) --version | sed 1q`'"' >>
version.go.tmp
echo 'const theGoarch = "'$(GOARCH)'"' >> version.go.tmp
echo 'const theGoos = "'$(GOOS)'"' >> version.go.tmp
- $(SHELL) $(srcdir)/../move-if-change version.go.tmp version.go
+ $(SHELL) $(srcdir)/mvifdiff.sh version.go.tmp version.go
$(STAMP) $@
go_sort_files = \
@@ -1791,14 +1791,14 @@ s-libcalls: libcalls-list go/syscall/mks
rm -f libcalls.go.tmp
files=`echo $^ | sed -e 's/libcalls-list//' -e 's|[^
]*go/syscall/mksyscall.awk||'`; \
$(AWK) -f $(srcdir)/go/syscall/mksyscall.awk $${files} > libcalls.go.tmp
- $(SHELL) $(srcdir)/../move-if-change libcalls.go.tmp libcalls.go
+ $(SHELL) $(srcdir)/mvifdiff.sh libcalls.go.tmp libcalls.go
$(STAMP) $@
libcalls-list: s-libcalls-list; @true
s-libcalls-list: Makefile
rm -f libcalls-list.tmp
echo $(go_base_syscall_files) > libcalls-list.tmp
- $(SHELL) $(srcdir)/../move-if-change libcalls-list.tmp libcalls-list
+ $(SHELL) $(srcdir)/mvifdiff.sh libcalls-list.tmp libcalls-list
$(STAMP) $@
syscall_arch.go: s-syscall_arch; @true
@@ -1807,13 +1807,13 @@ s-syscall_arch: Makefile
echo "package syscall" > syscall_arch.go.tmp
echo 'const ARCH = "'$(GOARCH)'"' >> syscall_arch.go.tmp
echo 'const OS = "'$(GOOS)'"' >> syscall_arch.go.tmp
- $(SHELL) $(srcdir)/../move-if-change syscall_arch.go.tmp syscall_arch.go
+ $(SHELL) $(srcdir)/mvifdiff.sh syscall_arch.go.tmp syscall_arch.go
$(STAMP) $@
sysinfo.go: s-sysinfo; @true
s-sysinfo: $(srcdir)/mksysinfo.sh config.h
CC="$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS)
$(CPPFLAGS) $(OSCFLAGS)" $(SHELL) $(srcdir)/mksysinfo.sh
- $(SHELL) $(srcdir)/../move-if-change tmp-sysinfo.go sysinfo.go
+ $(SHELL) $(srcdir)/mvifdiff.sh tmp-sysinfo.go sysinfo.go
$(STAMP) $@
# The epoll struct has an embedded union and is packed on x86_64,
@@ -1841,7 +1841,7 @@ s-epoll: Makefile
exit 1; ;; \
esac
echo '}' >> epoll.go.tmp
- $(SHELL) $(srcdir)/../move-if-change epoll.go.tmp epoll.go
+ $(SHELL) $(srcdir)/mvifdiff.sh epoll.go.tmp epoll.go
$(STAMP) $@
if LIBGO_IS_LINUX
Index: libgo/mvifdiff.sh
===================================================================
--- libgo/mvifdiff.sh (revision 0)
+++ libgo/mvifdiff.sh (working copy)
@@ -0,0 +1,15 @@
+#!/bin/sh
+
+# Copyright 2014 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# The mvifdiff.sh script works like the mv(1) command, except
+# that it does not touch the destination file if its contents
+# are the same as the source file.
+
+if cmp -s "$1" "$2" ; then
+ rm "$1"
+else
+ mv "$1" "$2"
+fi
