On Tue, 25 Jun 2019 at 06:08, Peter Eisentraut < peter.eisentr...@2ndquadrant.com> wrote:
> New thread continuing from > < > https://www.postgresql.org/message-id/d4903af2-e7b7-b551-71f8-3e4a6bdc2...@2ndquadrant.com > >. > > Here is a extended version of Álvaro's patch that adds an errbacktrace() > function. You can do two things with this: > > - Manually attach it to an ereport() call site that you want to debug. > > - Set a configuration parameter like backtrace_function = 'int8in' to > debug ereport()/elog() calls in a specific function. > > There was also mention of settings that would automatically produce > backtraces for PANICs etc. Those could surely be added if there is > enough interest. > > For the implementation, I support both backtrace() provided by the OS as > well as using libunwind. The former seems to be supported by a number > of platforms, including glibc, macOS, and FreeBSD, so maybe we don't > need the libunwind suport. I haven't found any difference in quality in > the backtraces between the two approaches, but surely that is highly > dependent on the exact configuration. > > I would welcome testing in all direction with this, to see how well it > works in different circumstances. > > Hi Peter, This is certainly a very useful thing. Sadly, it doesn't seem to compile when trying to use libunwind. I tried it in a Debian 9 machine with gcc 6.3.0 and debian says i installed libunwind8 (1.1) ./configure --prefix=/home/jcasanov/Documentos/pgdg/pgbuild/pg13 --enable-debug --enable-profiling --enable-cassert --enable-depend --with-libunwind at make i get these errors: """ utils/error/elog.o: En la función `set_backtrace': /home/jcasanov/Documentos/pgdg/projects/postgresql/src/backend/utils/error/elog.c:847: referencia a `_Ux86_64_getcontext' sin definir /home/jcasanov/Documentos/pgdg/projects/postgresql/src/backend/utils/error/elog.c:848: referencia a `_Ux86_64_init_local' sin definir /home/jcasanov/Documentos/pgdg/projects/postgresql/src/backend/utils/error/elog.c:850: referencia a `_Ux86_64_step' sin definir /home/jcasanov/Documentos/pgdg/projects/postgresql/src/backend/utils/error/elog.c:861: referencia a `_Ux86_64_get_reg' sin definir /home/jcasanov/Documentos/pgdg/projects/postgresql/src/backend/utils/error/elog.c:862: referencia a `_Ux86_64_get_proc_name' sin definir collect2: error: ld returned 1 exit status make[2]: *** [postgres] Error 1 make[1]: *** [all-backend-recurse] Error 2 make: *** [all-src-recurse] Error 2 """ -- Jaime Casanova www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
