ld: cannot find atomic

debian

Hello!
I was cross-compile Qt-6.2.0 for mipsel, Qt was found external libatomic and write this is to prl-file

libQt6Core.prl

QMAKE_PRL_BUILD_DIR = /tmp/firmware/build-sml723x/qtbase-6.2.0/src/corelib
QMAKE_PRL_TARGET = libQt6Core.so
QMAKE_PRL_CONFIG = shared
QMAKE_PRL_VERSION = 6.2.0
QMAKE_PRL_LIBS = -latomic
QMAKE_PRL_LIBS_FOR_CMAKE = -latomic

libQt6Network.prl

QMAKE_PRL_BUILD_DIR = /tmp/firmware/build-sml723x/qtbase-6.2.0/src/network
QMAKE_PRL_TARGET = libQt6Network.so
QMAKE_PRL_CONFIG = shared
QMAKE_PRL_VERSION = 6.2.0
QMAKE_PRL_LIBS = $$[QT_INSTALL_LIBS]/libQt6Core.so -latomic
QMAKE_PRL_LIBS_FOR_CMAKE = $$[QT_INSTALL_LIBS]/libQt6Core.so;-latomic

Now I try rebuild app, it use pro-file, but at link is fail with message ld: cannot find atomic: No such file or directory
I was inspect Makefile and found strange

....................
LIBS          = $(SUBLIBS) -L/tmp/firmware/staging_sml723x/usr/lib -L../qmap_parser -lqmapparser /tmp/firmware/staging_sml723x/qt6_bmips4380/lib/libQt6Gui.so /tmp/firmware/staging_sml723x/qt6_bmips4380/lib/libQt6Core.so -latomic -lpthread atomic  -Wl,-rpath-link,/tmp/firmware/staging_sml723x/usr/lib

After this I run qmake at debug mode and it output contain follow lines

................
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:20: LD_USES := LIBATOMIC
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:21: entering loop for nu 
over LIBATOMIC
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:21: loop iteration "LIBAT
OMIC"
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:21: entering block
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:22: NOT
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:22: evaluating test funct
ion "defined"
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:22: calling built-in defi
ned(QMAKE_LIBS_LIBATOMIC, var)
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:22: test function returne
d true
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:22: AND
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:23: skipped test function
 "error"
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:25: calling built-in $$ev
al(QMAKE_LIBDIR_LIBATOMIC)
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:25: QMAKE_LIBDIR := /tmp/
firmware/staging_sml723x/usr/lib
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:27: condition "android" i
s false
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:27: taking 'else' branch
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:27: entering block
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:31: condition "debug" is 
false
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:31: taking 'else' branch
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:31: entering block
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:34: calling built-in $$ev
al(QMAKE_LIBS_LIBATOMIC_RELEASE)
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:34: calling built-in $$ev
al(QMAKE_LIBS_LIBATOMIC)
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:34: LIBS := /tmp/firmware/staging_sml723x/qt6_bmips4380/lib/libQt6Core.so -lpthread atomic
DEBUG 1: /tmp/firmware/staging_sml723x/qt6_bmips4380/mkspecs/features/qmake_use.prf:34: leaving block, okey=true
...........

Look like what qmake_use.prf add atomic to list of libraries.

How can I fix this is?
Thnak you.

debian

My workaround

sed 's/atomic/-latomic/' --in-place=.org $(QT_INSTALL_DIR)/mkspecs/modules/qt_lib_core_private.pri

https://bugreports.qt.io/browse/QTBUG-97728

kshegunov

@debian said in ld: cannot find atomic:

How can I fix this is?

Install the libatomic library package.

debian

Sorry, I don't understand you.
Qt can't be build without atomic support, so this is support present, but it present as external library

$ find toolchain/mipsel-rtk-linux-uclibc/ -name *atomic.so*
toolchain/mipsel-rtk-linux-uclibc/mipsel-rtk-linux-uclibc/lib/libatomic.so
toolchain/mipsel-rtk-linux-uclibc/mipsel-rtk-linux-uclibc/lib/libatomic.so.1.2.0
toolchain/mipsel-rtk-linux-uclibc/mipsel-rtk-linux-uclibc/lib/libatomic.so.1
toolchain/mipsel-rtk-linux-uclibc/mipsel-rtk-linux-uclibc/sysroot/lib/libatomic.so
toolchain/mipsel-rtk-linux-uclibc/mipsel-rtk-linux-uclibc/sysroot/lib/libatomic.so.1.2.0
toolchain/mipsel-rtk-linux-uclibc/mipsel-rtk-linux-uclibc/sysroot/lib/libatomic.so.1

Problem in incorrect addititonal library name, LIBS contain correct -latomic and incorrect atomic.
Question - why incorrect library name present at LIBS?

debian

I think I found atomic source, this is mkspecs/modules/qt_lib_core_private.pri

..............
QMAKE_LIBS_LIBATOMIC = atomic
.............

I was change this is to QMAKE_LIBS_LIBATOMIC = -latomic and problem was solved

debian

My workaround

sed 's/atomic/-latomic/' --in-place=.org $(QT_INSTALL_DIR)/mkspecs/modules/qt_lib_core_private.pri

https://bugreports.qt.io/browse/QTBUG-97728

kshegunov

@debian said in ld: cannot find atomic:

Problem in incorrect addititonal library name, LIBS contain correct -latomic and incorrect atomic.

Sorry missed that. No idea on the question. The qmake feature appears to be incorrect in some way, but I have no clue why.