[fix](build) fix duplicate symbol errors when compiling BE UT with Clang #60504
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Problem: When running `./run-be-ut.sh` without the `--coverage` flag using Clang compiler, the build fails with duplicate symbol errors: ld.lld: error: duplicate symbol: __gcov_fork >>> defined in libgcov.a(libgcov-interface.o) >>> defined in libclang_rt.profile-x86_64.a(GCDAProfiling.o) Root cause analysis: PR apache#59543 introduced a condition in be/CMakeLists.txt to guard GCC-style coverage flags (`-fprofile-arcs -ftest-coverage -lgcov`): if (NOT (ENABLE_CLANG_COVERAGE STREQUAL "ON" AND COMPILER_CLANG)) The intent was to skip GCC coverage when Clang coverage is active. However, this condition has a logic flaw. When using Clang without `--coverage`: - ENABLE_CLANG_COVERAGE = OFF (default, set in run-be-ut.sh line 88) - COMPILER_CLANG = true The condition evaluates as: NOT (OFF AND true) = NOT (false) = true So GCC coverage flags are still added even when using Clang. Clang then implicitly links libclang_rt.profile (which provides its own implementation of __gcov_fork, __gcov_reset, etc.), causing duplicate symbol conflicts with the explicitly linked libgcov.a. Before PR apache#59543, coverage flags were unconditionally added for all compilers in MAKE_TEST mode — which also had the same issue with Clang. Fix: Replace the condition with `if (COMPILER_GCC)` so that GCC-style coverage flags are only added when actually using GCC compiler. This cleanly separates the two coverage mechanisms: - GCC compiler → automatic GCC coverage via -fprofile-arcs + libgcov - Clang compiler → no coverage by default; use --coverage flag to enable Clang coverage via -fprofile-instr-generate | Scenario | Before apache#59543 | After apache#59543 (bug) | This fix | |----------------------|---------------|--------------------|-------------| | GCC, no --coverage | GCC coverage | GCC coverage | GCC coverage| | GCC, --coverage | GCC coverage | GCC coverage | GCC coverage| | Clang, no --coverage | GCC cov (bad) | GCC cov (bad) | No coverage | | Clang, --coverage | GCC+Clang(bad)| Clang coverage | Clang cov |
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run buildall |
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Thank you for your contribution to Apache Doris. Please clearly describe your PR:
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TPC-H: Total hot run time: 31568 ms |
ClickBench: Total hot run time: 28.69 s |
BE UT Coverage ReportIncrement line coverage Increment coverage report
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gavinchou
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Feb 4, 2026
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PR approved by at least one committer and no changes requested. |
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PR approved by anyone and no changes requested. |
zclllyybb
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Feb 4, 2026
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BE Regression && UT Coverage ReportIncrement line coverage Increment coverage report
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Problem:
When running
./run-be-ut.shwithout the--coverageflag using Clang compiler, the build fails with duplicate symbol errors:ld.lld: error: duplicate symbol: __gcov_fork
Root cause analysis:
PR #59543 introduced a condition in be/CMakeLists.txt to guard GCC-style coverage flags (
-fprofile-arcs -ftest-coverage -lgcov):if (NOT (ENABLE_CLANG_COVERAGE STREQUAL "ON" AND COMPILER_CLANG))
The intent was to skip GCC coverage when Clang coverage is active. However, this condition has a logic flaw. When using Clang without
--coverage:The condition evaluates as:
NOT (OFF AND true) = NOT (false) = true
So GCC coverage flags are still added even when using Clang. Clang then implicitly links libclang_rt.profile (which provides its own implementation of __gcov_fork, __gcov_reset, etc.), causing duplicate symbol conflicts with the explicitly linked libgcov.a.
Before PR #59543, coverage flags were unconditionally added for all compilers in MAKE_TEST mode — which also had the same issue with Clang.
Fix:
Replace the condition with
if (COMPILER_GCC)so that GCC-style coverage flags are only added when actually using GCC compiler. This cleanly separates the two coverage mechanisms:What problem does this PR solve?
Issue Number: close #xxx
Related PR: #xxx
Problem Summary:
Release note
None
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Behavior changed:
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