Re: pkg/57445: firefox crashes on startup

[Taylor R Campbell <riastradh%NetBSD.org@localhost>]

The following reply was made to PR pkg/57445; it has been noted by GNATS.

From: Taylor R Campbell <riastradh%NetBSD.org@localhost>
To: Martin Husemann <martin%NetBSD.org@localhost>
Cc: gnats-bugs%NetBSD.org@localhost, joerg%NetBSD.org@localhost
Subject: Re: pkg/57445: firefox crashes on startup
Date: Thu, 1 Jun 2023 11:54:00 +0000

 Here's the relevant excerpts from the log:
 
 search object 0x70ee11e74400 (/usr/X11R7/lib/libglapi.so.1) for _glapi_tls_=
 Context
 check "_glapi_tls_Context" vs "_glapi_tls_Context" in /usr/X11R7/lib/libgla=
 pi.so.1
 /usr/X11R7/lib/libglapi.so.1: static tls offset 0x1840 size 16
 TPOFF64 _glapi_tls_Context in /usr/X11R7/lib/libglapi.so.1 --> 0xffffffffff=
 ffe7c0
 ...
 search object 0x70ee11e75000 (/usr/X11R7/lib/libGL.so) for _glapi_tls_Conte=
 xt
 check "_glapi_tls_Context" vs "glMultiTexCoord3ivARB" in /usr/X11R7/lib/lib=
 GL.so
 check "_glapi_tls_Context" vs "_glapi_tls_Context" in /usr/X11R7/lib/libGL.=
 so
 TPOFF64 _glapi_tls_Context in /usr/X11R7/lib/modules/dri/swrast_dri.so --> =
 0xffffffffffffe7a8
 ...
 obj 0x70ee11e74400 dtv 0x70ee1135e030 tlsoffset 6208
 obj 0x70ee11e75000 dtv 0x70ee03fae018 tlsoffset 6232
 ...
 u_current_set_context(0x70ee03e57dc0) thread 0x70ee11411400 lwp 1752, &_gla=
 pi_tls_Context: 0x70ee1135e030 (value: 0x70ee03e57dc0)
 &_glapi_tls_Context: 0x70ee1135e018 (value: 0x0)
 
 So there are two definitions of the symbol _glapi_tls_Context, one in
 libglapi and one in libGL.
 
 - On initial process execution, ld.elf_so resolves a reference to
   _glapi_tls_Context in libglapi to the definition in libglapi, at tls
   offset 6208 =3D 0x1840, which in lwp 1752 is at 0x70ee1135e030.
 
   This is what is used by u_current_set_context in libglapi, in
   xsrc/external/mit/MesaLib.old/dist/src/mapi/u_current.c, defined in
   the same file.
 
 - On dlopen of swrast_dri.so, however, ld.elf_so resolves a reference
   to _glapi_tls_Context in swrast_dri.so to the definition in libGL,
   at tls offset 6232 =3D 0x1858, which in lwp 1752 is at 0x70ee1135e018.
 
   This is what is used by _mesa_GetError in swrast_dri.so, in
   xsrc/external/mit/MesaLib.old/dist/src/mesa/main/getstring.c,
   defined in xsrc/external/mit/MesaLib.old/dist/src/glx/glxcurrent.c.
 
 (Note: static tls offsets are negative, which is why a higher tls
 offset leads to a lower virtual address in the same thread's tcb.)