| Message ID | 20240315142926.3832940-2-richard.purdie@linuxfoundation.org |
|---|---|
| State | Accepted, archived |
| Commit | 5ec2bc7ef663db4c04c85eee518297d442556481 |
| Headers | show |
| Series | [1/2] expat: Upgrade 2.6.1 -> 2.6.2 | expand |
On Fri, Mar 15, 2024 at 7:29 AM Richard Purdie <richard.purdie@linuxfoundation.org> wrote: > > With newer glibc versions, pthread was merged into the main library so there is > no longer any need to link with -lpthread. On newer systems this means that linker > flag is dropped from places like pkgconfig .pc files. If uninative then uses this > newer library on an older system, the flag is missing and linker errors about missing > symbols occur. > > Adding the linkage unconditionally to our uninative linking flags avoids that problem > at a potential cost of slight over linking. > There is another unintended consequence of linking pthreads unconditionally on older versions where certain functions which are required to be thread-safe are implemented as weak stubs in libc so single threaded programs do not incur the cost of ensuring thread safety, but when pthread it linked in, it will replace these stubs with thread safe versions which are correct in muti-threaded env but incur performance cost. I do not know how much of this is going to impact the uninative stuff but I thought I would mention it for reference. > Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org> > --- > meta/classes-global/uninative.bbclass | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/meta/classes-global/uninative.bbclass b/meta/classes-global/uninative.bbclass > index 9b8b4565dd4..d05b61c48eb 100644 > --- a/meta/classes-global/uninative.bbclass > +++ b/meta/classes-global/uninative.bbclass > @@ -143,8 +143,8 @@ def enable_uninative(d): > d.setVar("NATIVELSBSTRING", "universal%s" % oe.utils.host_gcc_version(d)) > d.appendVar("SSTATEPOSTUNPACKFUNCS", " uninative_changeinterp") > d.appendVarFlag("SSTATEPOSTUNPACKFUNCS", "vardepvalueexclude", "| uninative_changeinterp") > - d.appendVar("BUILD_LDFLAGS", " -Wl,--allow-shlib-undefined -Wl,--dynamic-linker=${UNINATIVE_LOADER}") > - d.appendVarFlag("BUILD_LDFLAGS", "vardepvalueexclude", "| -Wl,--allow-shlib-undefined -Wl,--dynamic-linker=${UNINATIVE_LOADER}") > + d.appendVar("BUILD_LDFLAGS", " -Wl,--allow-shlib-undefined -Wl,--dynamic-linker=${UNINATIVE_LOADER} -Wl,-lpthread") > + d.appendVarFlag("BUILD_LDFLAGS", "vardepvalueexclude", "| -Wl,--allow-shlib-undefined -Wl,--dynamic-linker=${UNINATIVE_LOADER} -Wl,-lpthread") > d.appendVarFlag("BUILD_LDFLAGS", "vardepsexclude", "UNINATIVE_LOADER") > d.prependVar("PATH", "${UNINATIVE_STAGING_DIR}-uninative/${BUILD_ARCH}-linux${bindir_native}:") > > -- > 2.40.1 > > > -=-=-=-=-=-=-=-=-=-=-=- > Links: You receive all messages sent to this group. > View/Reply Online (#197132): https://lists.openembedded.org/g/openembedded-core/message/197132 > Mute This Topic: https://lists.openembedded.org/mt/104948451/1997914 > Group Owner: openembedded-core+owner@lists.openembedded.org > Unsubscribe: https://lists.openembedded.org/g/openembedded-core/unsub [raj.khem@gmail.com] > -=-=-=-=-=-=-=-=-=-=-=- >
diff --git a/meta/classes-global/uninative.bbclass b/meta/classes-global/uninative.bbclass index 9b8b4565dd4..d05b61c48eb 100644 --- a/meta/classes-global/uninative.bbclass +++ b/meta/classes-global/uninative.bbclass @@ -143,8 +143,8 @@ def enable_uninative(d): d.setVar("NATIVELSBSTRING", "universal%s" % oe.utils.host_gcc_version(d)) d.appendVar("SSTATEPOSTUNPACKFUNCS", " uninative_changeinterp") d.appendVarFlag("SSTATEPOSTUNPACKFUNCS", "vardepvalueexclude", "| uninative_changeinterp") - d.appendVar("BUILD_LDFLAGS", " -Wl,--allow-shlib-undefined -Wl,--dynamic-linker=${UNINATIVE_LOADER}") - d.appendVarFlag("BUILD_LDFLAGS", "vardepvalueexclude", "| -Wl,--allow-shlib-undefined -Wl,--dynamic-linker=${UNINATIVE_LOADER}") + d.appendVar("BUILD_LDFLAGS", " -Wl,--allow-shlib-undefined -Wl,--dynamic-linker=${UNINATIVE_LOADER} -Wl,-lpthread") + d.appendVarFlag("BUILD_LDFLAGS", "vardepvalueexclude", "| -Wl,--allow-shlib-undefined -Wl,--dynamic-linker=${UNINATIVE_LOADER} -Wl,-lpthread") d.appendVarFlag("BUILD_LDFLAGS", "vardepsexclude", "UNINATIVE_LOADER") d.prependVar("PATH", "${UNINATIVE_STAGING_DIR}-uninative/${BUILD_ARCH}-linux${bindir_native}:")
With newer glibc versions, pthread was merged into the main library so there is no longer any need to link with -lpthread. On newer systems this means that linker flag is dropped from places like pkgconfig .pc files. If uninative then uses this newer library on an older system, the flag is missing and linker errors about missing symbols occur. Adding the linkage unconditionally to our uninative linking flags avoids that problem at a potential cost of slight over linking. Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org> --- meta/classes-global/uninative.bbclass | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)