I was actually wondering about this, as in some cases valgrind errors appear and sometimes they don't, but I didn't dig into it too deeply.
Here's my workaround, FWIW, which shows some output for that test on master. I don't see any output when I just run the tests like this: VALGRIND=1 make -f gmakefile.test test globsearch="dm_impls_plex_tests-ex1_fluent_2" But I do see something if I do this to find any non-empty .err files: find $PETSC_ARCH/tests -name *.err ! -size 0 And then I see these valgrind warnings after copy-pasting the path: $ cat arch-master-extra-opt/tests/dm/impls/plex/examples/tests/runex1_fluent_2/runex1_fluent_2.err ==4990== Conditional jump or move depends on uninitialised value(s) ==4990== at 0x4C3705A: rawmemchr (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so) ==4990== by 0x7687351: _IO_str_init_static_internal (strops.c:41) ==4990== by 0x767878C: vsscanf (iovsscanf.c:40) ==4990== by 0x76721A3: sscanf (sscanf.c:32) ==4990== by 0x588147D: DMPlexCreateFluent_ReadSection (plexfluent.c:105) ==4990== by 0x5882E3A: DMPlexCreateFluent (plexfluent.c:246) ==4990== by 0x588492F: DMPlexCreateFluentFromFile (plexfluent.c:30) ==4990== by 0x577E2B7: DMPlexCreateFromFile (plexcreate.c:3254) ==4990== by 0x10BEDF: CreateMesh (ex1.c:170) ==4990== by 0x10A20B: main (ex1.c:430) ==4990== Uninitialised value was created by a stack allocation ==4990== at 0x5881313: DMPlexCreateFluent_ReadSection (plexfluent.c:96) ==4990== ==4990== Use of uninitialised value of size 8 ==4990== at 0x766276F: _IO_vfscanf (vfscanf.c:633) ==4990== by 0x767879C: vsscanf (iovsscanf.c:41) ==4990== by 0x76721A3: sscanf (sscanf.c:32) ==4990== by 0x588147D: DMPlexCreateFluent_ReadSection (plexfluent.c:105) ==4990== by 0x5882E3A: DMPlexCreateFluent (plexfluent.c:246) ==4990== by 0x588492F: DMPlexCreateFluentFromFile (plexfluent.c:30) ==4990== by 0x577E2B7: DMPlexCreateFromFile (plexcreate.c:3254) ==4990== by 0x10BEDF: CreateMesh (ex1.c:170) ==4990== by 0x10A20B: main (ex1.c:430) ==4990== Uninitialised value was created by a stack allocation ==4990== at 0x5881313: DMPlexCreateFluent_ReadSection (plexfluent.c:96) ==4990== ==4990== Conditional jump or move depends on uninitialised value(s) ==4990== at 0x766277B: _IO_vfscanf (vfscanf.c:630) ==4990== by 0x767879C: vsscanf (iovsscanf.c:41) ==4990== by 0x76721A3: sscanf (sscanf.c:32) ==4990== by 0x588147D: DMPlexCreateFluent_ReadSection (plexfluent.c:105) ==4990== by 0x5882E3A: DMPlexCreateFluent (plexfluent.c:246) ==4990== by 0x588492F: DMPlexCreateFluentFromFile (plexfluent.c:30) ==4990== by 0x577E2B7: DMPlexCreateFromFile (plexcreate.c:3254) ==4990== by 0x10BEDF: CreateMesh (ex1.c:170) ==4990== by 0x10A20B: main (ex1.c:430) ==4990== Uninitialised value was created by a stack allocation ==4990== at 0x5881313: DMPlexCreateFluent_ReadSection (plexfluent.c:96) ==4990== > Am 07.12.2019 um 21:45 schrieb Matthew Knepley <knep...@gmail.com>: > > I am trying to clean up valgrind errors. However this one > > dm_impls_plex_tests-ex1_fluent_2 > > is valgrind clean on my machine. Does anyone get it to output something? > > Thanks, > > Matt > > -- > What most experimenters take for granted before they begin their experiments > is infinitely more interesting than any results to which their experiments > lead. > -- Norbert Wiener > > https://www.cse.buffalo.edu/~knepley/ <http://www.cse.buffalo.edu/~knepley/>