thanks to jmcneill for suggesting dlerror(); perhaps we need to remove -DGLX_USE_TLS. it otherwise uses TLS via pthread.
/usr/X11R7/lib/libGL.so: Use of initialized Thread Local Storage with model initial-exec and dlopen is not supported I'm going to test Index: libmesa.mk =================================================================== RCS file: /cvsroot/src/external/mit/xorg/lib/libmesa.mk,v retrieving revision 1.6 diff -u -r1.6 libmesa.mk --- libmesa.mk 3 Apr 2019 15:26:34 -0000 1.6 +++ libmesa.mk 9 Apr 2019 10:37:54 -0000 @@ -521,7 +521,6 @@ -DHAVE_LIBDRM -DGLX_USE_DRM \ -DGLX_INDIRECT_RENDERING \ -DGLX_DIRECT_RENDERING \ - -DGLX_USE_TLS \ -DHAVE_X11_PLATFORM \ -DHAVE_DRM_PLATFORM \ -DENABLE_SHADER_CACHE \ Index: libGL/Makefile =================================================================== RCS file: /cvsroot/src/external/mit/xorg/lib/libGL/Makefile,v retrieving revision 1.23 diff -u -r1.23 Makefile --- libGL/Makefile 10 Mar 2019 10:51:58 -0000 1.23 +++ libGL/Makefile 9 Apr 2019 10:37:55 -0000 @@ -164,7 +164,7 @@ -DHAVE_FUNC_ATTRIBUTE_NORETURN=1 -DHAVE_ENDIAN_H=1 -DHAVE_DLADDR=1 \ -DHAVE_CLOCK_GETTIME=1 -DHAVE_PTHREAD_PRIO_INHERIT=1 \ -DHAVE_PTHREAD=1 -DENABLE_ST_OMX_BELLAGIO=0 -DENABLE_ST_OMX_TIZONIA=0 \ - -DHAVE_TIMESPEC_GET -DGLX_USE_TLS + -DHAVE_TIMESPEC_GET .include "../asm.mk" Index: libglapi/Makefile =================================================================== RCS file: /cvsroot/src/external/mit/xorg/lib/libglapi/Makefile,v retrieving revision 1.4 diff -u -r1.4 Makefile --- libglapi/Makefile 10 Mar 2019 10:51:58 -0000 1.4 +++ libglapi/Makefile 9 Apr 2019 10:37:55 -0000 @@ -68,7 +68,6 @@ -DGLX_USE_DRM \ -DGLX_INDIRECT_RENDERING \ -DGLX_DIRECT_RENDERING \ - -DGLX_USE_TLS \ -DHAVE_X11_PLATFORM \ -DHAVE_DRM_PLATFORM \ -DENABLE_SHADER_CACHE \