libaio: Link against libgcc and libc to avoid unresolved symbols
PATCH 1/1 libaio: Link against libgcc and libc to avoid unresolved symbols
Fix proposed by Debian developers that makes sure all libgcc.a sybols used in libaio.so are built-in.
Fixes build failures of blktrace, lvm2 and the like users of libaio.
A couple of examples below:
blktrace: http://autobuild.buildroot.net/results/5528ab59f1939a7eff7e85318f3b36283019cc50/ lvm2: http://autobuild.buildroot.net/results/a5dfc87f94b97135e5cc84f6a876114891ed9dd9/
And since we solve the problem in libaio sources there's no need to mess with compilation flags in Buildroot, thus partially revert commit ce6536ae500f ("libaio: work-around for PowerPC issue").
Signed-off-by Thomas Petazzoni <[email protected]>
Signed-off-by Alexey Brodkin <[email protected]>
--- ...gainst-libgcc-to-avoid-unresolved-symbols.patch | 57 ++++++++++++++++++++++ package/libaio/libaio.mk | 6 --- 2 files changed, 57 insertions(+), 6 deletions(-) create mode 100644 package/libaio/0003-Link-against-libgcc-to-avoid-unresolved-symbols.patch
package/libaio/0003-Link-against-libgcc-to-avoid-unresolved-symbols.patch new file +57 -0
@@ -0,0 +1,57 @@ +From 672eaebd131c789a528e3a9cd089b4b69a82012b Mon Sep 17 00:00:00 2001 +From: Guillem Jover <[email protected]> +Date: Fri, 28 Sep 2018 13:15:54 +0300 +Subject: [PATCH] Link against libgcc to avoid unresolved symbols + +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: +--------------------------->8---------------------- +hidden symbol '__ld_r13_to_r15_ret' in .../libgcc.a(_millicodethunk_ret.o) is referenced by DSO +--------------------------->8---------------------- + +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]. + +Was submitted upstream via pull-request [5]. + +[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/ +[5] https://pagure.io/libaio/pull-request/7 + +Signed-off-by: Guillem Jover <[email protected]> +Signed-off-by: Alexey Brodkin <[email protected]> +--- + src/Makefile | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/src/Makefile b/src/Makefile +index eadb336b47e3..5911c810c766 100644 +--- a/src/Makefile ++++ b/src/Makefile +@@ -3,7 +3,7 @@ includedir=$(prefix)/include + libdir=$(prefix)/lib + + CFLAGS ?= -g -fomit-frame-pointer -O2 +-CFLAGS += -nostdlib -nostartfiles -Wall -I. -fPIC ++CFLAGS += -Wall -I. -fPIC + SO_CFLAGS=-shared $(CFLAGS) + L_CFLAGS=$(CFLAGS) + LINK_FLAGS= +-- +2.17.1 +
package/libaio/libaio.mk +0 -6
@@ -16,12 +16,6 @@ ifeq ($(BR2_STATIC_LIBS),y) LIBAIO_CONFIGURE_OPTS += ENABLE_SHARED=0 endif -# On PowerPC, a weird toolchain issue causes -Os builds to produce -# references to hidden symbols, so we're forcing -O2 -ifeq ($(BR2_powerpc),y) -LIBAIO_CONFIGURE_OPTS += CFLAGS="$(subst -Os,-O2,$(TARGET_CFLAGS))" -endif - define LIBAIO_BUILD_CMDS $(LIBAIO_CONFIGURE_OPTS) $(TARGET_MAKE_ENV) $(MAKE) -C $(@D) endef
Signature · 1 line
2.16.2
Thomas Petazzoni
AppliedPATCH 1/1 libaio: Link against libgcc and libc to avoid unresolved symbols
Hello,
Quoted 13 lines · Alexey Brodkin
Fix proposed by Debian developers that makes sure all libgcc.a sybols used in libaio.so are built-in.
Fixes build failures of blktrace, lvm2 and the like users of libaio.
A couple of examples below:
blktrace: http://autobuild.buildroot.net/results/5528ab59f1939a7eff7e85318f3b36283019cc50/ lvm2: http://autobuild.buildroot.net/results/a5dfc87f94b97135e5cc84f6a876114891ed9dd9/And since we solve the problem in libaio sources there's no need to mess with compilation flags in Buildroot, thus partially revert commit
ce6536ae500f("libaio: work-around for PowerPC issue").
Quoted 7 lines
Signed-off-by Thomas Petazzoni <[email protected]>Signed-off-by Alexey Brodkin <[email protected]>--- ...gainst-libgcc-to-avoid-unresolved-symbols.patch | 57 ++++++++++++++++++++++ package/libaio/libaio.mk | 6 --- 2 files changed, 57 insertions(+), 6 deletions(-) create mode 100644 package/libaio/0003-Link-against-libgcc-to-avoid-unresolved-symbols.patch
Applied to master with a slightly tweaked commit log. Thanks!
Thomas
Signature · 3 lines
Thomas Petazzoni, CTO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com