Gtest: test_context_config.modify fails under Valgrind

[karasevb]

[----------] 4 tests from test_context_config, where TypeParam =
[ RUN      ] test_context_config.read_release <> <>
[       OK ] test_context_config.read_release (10 ms)
[ RUN      ] test_context_config.print <> <>
[       OK ] test_context_config.print (10 ms)
[ RUN      ] test_context_config.modify <> <>
**3465** [1617199293.251438] [0]     ucc_context.c:161  UCC  ERROR failed to modify CL "basic" configuration, name _UNKNOWN_FIELD, value _unknown_value
../../../test/gtest/core/test_context_config.cc:65: Failure
Expected: (std::string::npos) != (output.find("failed to modify")), actual: 18446744073709551615 vs 18446744073709551615
**3465** [1617199293.309419] [0]          ucc_cl.c:71   UCC  ERROR incorrect value is passed as part of UCC_CLS list: _unknown_cl
**3465** [1617199293.310071] [0]     ucc_context.c:145  UCC  ERROR failed to parse cls string: _unknown_cl
../../../test/gtest/core/test_context_config.cc:72: Failure
Expected: (std::string::npos) != (output.find("incorrect value")), actual: 18446744073709551615 vs 18446744073709551615
[  FAILED  ] test_context_config.modify, where TypeParam =  and GetParam() =  (83 ms)
[ RUN      ] test_context_config.modify_core <> <>
**3465** [1617199293.330501] [0]     ucc_context.c:137  UCC  ERROR failed to modify CORE configuration, name _UNKNOWN_FIELD, value _unknown_value
../../../test/gtest/core/test_context_config.cc:97: Failure
Expected: (std::string::npos) != (output.find("failed to modify")), actual: 18446744073709551615 vs 18446744073709551615
[  FAILED  ] test_context_config.modify_core, where TypeParam =  and GetParam() =  (12 ms)
[----------] 4 tests from test_context_config (121 ms total)

Tested with commit: f744574
Configure: --with-ucx (uses ucx debug build) --enable-gtest --without-cuda --enable-debug --with-valgrind

[Sergei-Lebedev]

@karasevb did you build UCX with "--with-valgrind" option? If yes, that issues happens because UCS uses valgrind printf which doesn't print to stdout. Thus gtest didn't captured output and test failed. Perhaps we should disable output check in the test and check only config read return status.

[karasevb]

@Sergei-Lebedev yes.
I used contrib/configure-devel to build, it includes --with-valgrind.