[PATCH] Drop -rdynamic from deleted-lib.so link step

[PATCH] Drop -rdynamic from deleted-lib.so link step

[Ulf Hermann]

-rdynamic is meant for ELF objects that need to export internal
symbols to libraries they link to, but deleted-lib.so does not link to
anything else and doesn't have any internal symbols.

Note that the "deleted" test program does link to deleted-lib.so, but
deleted-lib.so being a shared object, will automatically export the
(non-hidden) "libfunc" symbol anyway.

(This patch supersedes "[PATCH] Check if gcc supports -rdynamic and
don't use it if not" from 05/03/2017)

Signed-off-by: Ulf Hermann <ulf.hermann@qt.io>
---
 tests/ChangeLog   | 4 ++++
 tests/Makefile.am | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/tests/ChangeLog b/tests/ChangeLog
index 19a4c88d..0d5bee75 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,7 @@
+2017-08-18  Ulf Hermann <ulf.hermann@qt.io>
+
+	* Makefile.am: Drop -rdynamic from deleted_lib_so_LDFLAGS.
+
 2017-04-27  Ulf Hermann <ulf.hermann@qt.io>
 
 	* Makefile.am: Use fpie_CFLAGS and fpic_CFLAGS.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 6332a7c1..2eac8020 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -484,7 +484,7 @@ debuglink_LDADD = $(libdw) $(libelf)
 debugaltlink_LDADD = $(libdw) $(libelf)
 buildid_LDADD = $(libdw) $(libelf)
 deleted_LDADD = ./deleted-lib.so
-deleted_lib_so_LDFLAGS = -shared -rdynamic
+deleted_lib_so_LDFLAGS = -shared
 deleted_lib_so_CFLAGS = $(fpic_CFLAGS) -fasynchronous-unwind-tables
 aggregate_size_LDADD = $(libdw) $(libelf) $(argp_LDADD)
 peel_type_LDADD = $(libdw) $(libelf) $(argp_LDADD)
-- 
2.11.0

Re: [PATCH] Drop -rdynamic from deleted-lib.so link step

[Mark Wielaard]

On Fri, Aug 18, 2017 at 03:17:38PM +0200, Ulf Hermann wrote:
> -rdynamic is meant for ELF objects that need to export internal
> symbols to libraries they link to, but deleted-lib.so does not link to
> anything else and doesn't have any internal symbols.
> 
> Note that the "deleted" test program does link to deleted-lib.so, but
> deleted-lib.so being a shared object, will automatically export the
> (non-hidden) "libfunc" symbol anyway.

Applied, libfunc is indeed the only relevant symbol in this case.

Thanks,

Mark