libtool/m4
Pavel Raiskup 418129bc63 ARFLAGS: use 'cr' instead of 'cru' by default
In some GNU/Linux distributions people started to compile 'ar'
binary with --enable-deterministic-archives (binutils project).
That, however, in combination with our previous long time working
default AR_FLAGS=cru causes warnings on such installations:
ar: `u' modifier ignored since `D' is the default (see `U')

The 'u' option (at least with GNU binutils) did small optimization
during repeated builds because it instructed 'ar' to not
open/close unchanged *.o files and to rather read their contents
from old archive file.  However, its removal should not cause a
big performance hit for usual workflows.

Distributions started using --enable-deterministic-archives
knowing that it would disable the 'u', just to rather have a bit
more deterministic builds.

Also, to justify this change a bit more, keeping 'u' in ARFLAGS
could only result in many per-project changes to override
Libtool's ARFLAGS default, just to silent such warnings.

Fixes bug#19967.  Reported by Eric Blake.

* m4/libtool.m4 (_LT_PROG_AR): Default AR_FLAGS to 'cr'.
(_LT_REQUIRED_DARWIN_CHECKS): Use $AR_FLAGS instead 'cru' string.
* doc/libtool.texi: Do 's/ar cru/ar cr/' in whole documentation.
* NEWS: Document.
2015-09-26 18:00:16 +02:00
..
.gitignore libtoolize: rename libltdl/m4' directory to standard m4'. 2011-11-17 17:51:14 +07:00
autobuild.m4 maint: update copyright statements to include 2015. 2015-01-18 13:16:42 +00:00
libtool.m4 ARFLAGS: use 'cr' instead of 'cru' by default 2015-09-26 18:00:16 +02:00
lt~obsolete.m4 maint: update copyright statements to include 2015. 2015-01-18 13:16:42 +00:00
ltargz.m4 maint: update copyright statements to include 2015. 2015-01-18 13:16:42 +00:00
ltdl.m4 maint: update copyright statements to include 2015. 2015-01-18 13:16:42 +00:00
ltoptions.m4 maint: update copyright statements to include 2015. 2015-01-18 13:16:42 +00:00
ltsugar.m4 maint: update copyright statements to include 2015. 2015-01-18 13:16:42 +00:00
ltversion.in maint: update copyright statements to include 2015. 2015-01-18 13:16:42 +00:00
m4.m4 maint: update copyright statements to include 2015. 2015-01-18 13:16:42 +00:00