#7 Link against libgcc to avoid unresolved symbols
Merged 3 years ago by jmoyer. Opened 3 years ago by abrodkin.
abrodkin/libaio topic-libgcc  into  master

file modified
+1 -1
@@ -3,7 +3,7 @@ 



  CFLAGS ?= -g -fomit-frame-pointer -O2

- CFLAGS += -nostdlib -nostartfiles -Wall -I. -fPIC

+ CFLAGS += -Wall -I. -fPIC

  SO_CFLAGS=-shared $(CFLAGS)



We need to link agaisnt -lgcc, on at least hppa, PPC and ARC.
That's because in some corner-cases like compilation with -Os
on ARC and PPC so-called millicode (basically function prologue and
epilogue) implemented in libgcc.a is used. So we end up with
GLOBAL UNDEFINED symbol in libaio.so and then on linkage of the final
applicaiton LD fails to proceed saying:
hidden symbol '__ld_r13_to_r15_ret' in .../libgcc.a(_millicodethunk_ret.o) is referenced by DSO

Also it looks like in general it is not the best idea to use either
"-nostartfiles" or "-nostdlib" when linking shared libs because
default construtor/destructor functions won't be executed, see
"5.2. Library constructor and destructor functions" in [1]

So let's stop passing "-nostdlib" and "-nostartfiles" and get required
stuff built-in libaio.

Initial patch taken from Debian [2].

Fixes build failures in Buildroot like blktrace [3], lvm2 [4].

[1] http://tldp.org/HOWTO/Program-Library-HOWTO/miscellaneous.html
[2] https://sources.debian.org/patches/libaio/0.3.111-1/01_link_libs.patch/
[3] http://autobuild.buildroot.net/results/17461209755038a30118d76acb4f43469a22a139/
[4] http://autobuild.buildroot.net/results/a5dfc87f94b97135e5cc84f6a876114891ed9dd9/

Signed-off-by: Guillem Jover guillem@debian.org
Signed-off-by: Alexey Brodkin abrodkin@synopsys.com

Pull-Request has been merged by jmoyer

3 years ago