[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 Bug 87189 depends on bug 78017, which changed state. Bug 78017 Summary: weak reference usage in gthr-posix.h (__gthread*) is broken with new enough glibc (GTHREAD_USE_WEAK can be defined to 0 now) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78017 What|Removed |Added Status|NEW |RESOLVED Resolution|--- |FIXED
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 --- Comment #13 from Andrew Pinski --- *** Bug 114646 has been marked as a duplicate of this bug. ***
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 Andrew Pinski changed: What|Removed |Added Resolution|--- |DUPLICATE Status|UNCONFIRMED |RESOLVED --- Comment #12 from Andrew Pinski --- Dup. *** This bug has been marked as a duplicate of bug 78017 ***
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 Andrew Pinski changed: What|Removed |Added CC||hjl.tools at gmail dot com --- Comment #11 from Andrew Pinski --- *** Bug 114646 has been marked as a duplicate of this bug. ***
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 --- Comment #10 from Bruno Haible --- It is fixed in - glibc 2.35 + gcc 11.4 (verified on Ubuntu 22.04), - glibc 2.39 + gcc 13.2.1 (verified on Arch Linux 2024.04).
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 --- Comment #9 from Paul Pluzhnikov --- Thanks, H.J. https://sourceware.org/bugzilla/show_bug.cgi?id=5784 has a few references, and in particular https://sourceware.org/ml/libc-alpha/2012-09/msg00192.html is important to consider.
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 --- Comment #8 from H.J. Lu --- Here is a very old proposal: https://groups.google.com/forum/#!msg/generic-abi/K1lUiNsmM6c/Pl9-7ngPVXIJ I am not sure if it will completely fix: https://sourceware.org/bugzilla/show_bug.cgi?id=5784
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 --- Comment #7 from Jakub Jelinek --- gthr.h is used heavily e.g. in libstdc++, so your solution doesn't really work at all.
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 --- Comment #6 from Paul Pluzhnikov --- (In reply to Jakub Jelinek from comment #5) > Because it is very expensive. One impractical solution is to require '-pthread' on the compile and link line, and link a libgcc_mt that has non-weak references to pthread_* functions. This will force end users to finally build their programs with correct command line :-)
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 --- Comment #5 from Jakub Jelinek --- (In reply to Paul Pluzhnikov from comment #4) > (In reply to Jakub Jelinek from comment #3) > > This is a glibc bug > > I (obviously) disagree. > > , coming up with a set of weakref checks for gthr.h that > > would satisfy static linking of glibc and all possible combinations of > > included vs. non-included objects is impossible. > > If you call pthread_mutex_lock (or any other function) via weakref, then you > should ensure that the function is actually available. > > AFAICT, libgcc only calls a few pthread_* functions. Why is it hard to check > that *all* of them are present? Because it is very expensive. Each of those tests requires a dynamic relocation, GOT read every time it is checked, bloats the code size, etc.
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 --- Comment #4 from Paul Pluzhnikov --- (In reply to Jakub Jelinek from comment #3) > This is a glibc bug I (obviously) disagree. , coming up with a set of weakref checks for gthr.h that > would satisfy static linking of glibc and all possible combinations of > included vs. non-included objects is impossible. If you call pthread_mutex_lock (or any other function) via weakref, then you should ensure that the function is actually available. AFAICT, libgcc only calls a few pthread_* functions. Why is it hard to check that *all* of them are present? > E.g. Fedora/RHEL ld -r libpthread.a objects into a single exactly because of > this. That is a workaround, not a fix. And it has significant negative effects in the resulting program code size. > There are many dups of this both on the gcc side and glibc side. Well, I think GCC and GLIBC developers need to sit down and decide whose bug it is, and fix it once and for all :-)
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 --- Comment #3 from Jakub Jelinek --- This is a glibc bug, coming up with a set of weakref checks for gthr.h that would satisfy static linking of glibc and all possible combinations of included vs. non-included objects is impossible. E.g. Fedora/RHEL ld -r libpthread.a objects into a single exactly because of this. The other alternative is to add (for libpthread.a) dependencies in betweeh the *.o objects so that a reasonable set is always linked together, or just link with --whole-archive -lpthread --no-whole-archive. There are many dups of this both on the gcc side and glibc side.
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 Richard Biener changed: What|Removed |Added CC||jakub at gcc dot gnu.org, ||rguenth at gcc dot gnu.org --- Comment #2 from Richard Biener --- Hmm, "interesting" case. Not sure what to do about these...
[Bug libgcc/87189] libgcc/gthr-posix.h (__gthread_active_p) makes unwarranted assumptions about libpthread.a
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87189 --- Comment #1 from Paul Pluzhnikov --- Crash stack for reference: Program received signal SIGSEGV, Segmentation fault. 0x in ?? () (gdb) bt #0 0x in ?? () #1 0x00477f7c in __gthread_mutex_lock (__mutex=0x6a7380 ) at ./gthr-default.h:748 #2 __register_frame_info_bases (begin=, ob=0x6a2300 , tbase=, dbase=) at ../../../libgcc/unwind-dw2-fde.c:103 #3 0x00400acd in frame_dummy () #4 0x0001 in ?? () #5 0x0040194c in __libc_csu_init (argc=-9472, argc@entry=1, argv=argv@entry=0x7fffdc78, envp=0x7fffdc88) at elf-init.c:88 #6 0x00401170 in __libc_start_main (main=0x400add , argc=1, argv=0x7fffdc78, init=0x4018d0 <__libc_csu_init>, fini=0x401970 <__libc_csu_fini>, rtld_fini=0x0, stack_end=0x7fffdc68) at ../csu/libc-start.c:264 #7 0x004009fa in _start () at ../sysdeps/x86_64/start.S:120
