Re: [PATCH] Fix build with LDFLAGS="-Wl,--as-needed"
Lars Wendler <polynomial-c@gentoo.org> writes:
> Subject: Re: [PATCH] Fix build with LDFLAGS="-Wl,--as-needed"
Please identify what area you are touching, e.g.
Subject: contrib/svn-fe: avoid early $(EXTLIBS) on linker invocation
or whatever.
"Fix build" does not tell us why this change is needed; it does not say what breaks, how and most importantly why it breaks. Please have explanation in the commit message body, e.g.
When attempting to build svn-fe with LDFLAGS=-Wl,--as-needed,
I noticed that ... breaks in such and such way. This is
because you must not have X before Y due to Z.
Fix this by doing A, B and C, which makes sure X comes after
Y.or somesuch.
> Signed-off-by: Lars Wendler <polynomial-c@gentoo.org>
> ---
Show 13 quoted lines
> contrib/svn-fe/Makefile | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/contrib/svn-fe/Makefile b/contrib/svn-fe/Makefile
> index e8651aa..b90cf87 100644
> --- a/contrib/svn-fe/Makefile
> +++ b/contrib/svn-fe/Makefile
> @@ -74,7 +74,7 @@ endif
> endif
>
> svn-fe$X: svn-fe.o $(VCSSVN_LIB) $(XDIFF_LIB) $(GIT_LIB)
> - $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(EXTLIBS) -o $@ svn-fe.o $(LIBS)
> + $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ svn-fe.o $(LIBS) $(EXTLIBS)
I do not understand the original, which has
EXTLIBS =
GIT_LIB = ../../libgit.a
VCSSVN_LIB = ../../vcs-svn/lib.a
LIBS = $(VCSSVN_LIB) $(GIT_LIB) $(EXTLIBS)
i.e. it shouldn't be necessary to explicitly list EXTLIBS, as it already has LIBS at the end, which in turn has EXTLIBS at the end.
Which in turn means I do not understand your updated version, either. If having EXTLIBS before svn-fe.o is bad (and it is---a linker invocation lists *.o files that need to be linked first, and then libraries to find the symbols requested by those *.o files), wouldn't a fix be to just drop $(EXTLIBS)? Why is it necessary to list it twice?
