Antalya 25.8 - Fix CrashWriter to check empty endpoint before sending crash report

[CarlosFelipeOR]

This PR improves the fix for #1437 (previously fixed in #1438).

The original fix prevented the exception by not creating the CrashWriter instance when disabled, but this resulted in no logging when crashes occurred with reporting disabled.

This PR implements Option B: always create the instance and add an early return in sendError() when the endpoint is empty. This prevents the exception while providing informative logs (<Debug> CrashWriter: Not sending crash report (crash reporting is disabled)) when crashes happen with reporting disabled.

Changelog category (leave one):

• Not for changelog (changelog entry is not required)

CI/CD Options

Exclude tests:

• Fast test
• Integration Tests
• Stateless tests
• Stateful tests
• Performance tests
• All with ASAN
• All with TSAN
• All with MSAN
• All with UBSAN
• All with Coverage
• All with Aarch64
• All Regression
• Disable CI Cache

Regression jobs to run:

• Fast suites (mostly <1h)
• Aggregate Functions (2h)
• Alter (1.5h)
• Benchmark (30m)
• ClickHouse Keeper (1h)
• Iceberg (2h)
• LDAP (1h)
• Parquet (1.5h)
• RBAC (1.5h)
• SSL Server (1h)
• S3 (2h)
• Tiered Storage (2h)

[github-actions]

Workflow [PR], commit [72dc68f]

[CarlosFelipeOR]

QA Verification

Tested the fix by sending kill -SEGV to the server process and checking the crash logs.

Test Environment

• Version: 25.8.16.20001.altinityantalya
• Git Hash: d006751

Results ✅

PASSED - The fix works correctly:

• ✅ No BAD_ARGUMENTS exception occurred (previously would show: Code: 36. DB::Exception: Empty protocol in the URL. (BAD_ARGUMENTS))
• ✅ Expected log message appears: <Debug> CrashWriter: Not sending crash report (crash reporting is disabled)
• ✅ No attempt to send crash report with empty endpoint

Crash Log Output

The crash was handled correctly with the informative log message:

2026.03.10 17:30:17.091982 [ 2819855 ] {} <Trace> BaseDaemon: Received signal 11
2026.03.10 17:30:17.092122 [ 2819855 ] {} <Fatal> BaseDaemon: ########## Short fault info ############
2026.03.10 17:30:17.092153 [ 2819855 ] {} <Fatal> BaseDaemon: (version 25.8.16.20001.altinityantalya, build id: 3038DF0907550E746F1D3AE5782185C910FA9621, git hash: d0067516968b65e97dde5438b400226df32be1a6, architecture: x86_64) (from thread 2819804) Received signal 11
2026.03.10 17:30:17.092162 [ 2819855 ] {} <Fatal> BaseDaemon: Signal description: Segmentation fault
2026.03.10 17:30:17.092176 [ 2819855 ] {} <Fatal> BaseDaemon: Address: 0x3e8002b0b9e. Access: read. Unknown si_code.
2026.03.10 17:30:17.092197 [ 2819855 ] {} <Fatal> BaseDaemon: Stack trace: 0x0000737097a98d72 0x0000737097a9b7ed 0x00005b2cf902bf4f 0x00005b2cec6236cb 0x00005b2ce88a7b0a 0x00005b2cf8492666 0x00005b2ce888f4b0 0x00005b2ce888ca48 0x00005b2ce1aef61f 0x0000737097a2a1ca 0x0000737097a2a28b 0x00005b2ce1aee02e
2026.03.10 17:30:17.092205 [ 2819855 ] {} <Fatal> BaseDaemon: ########################################
2026.03.10 17:30:17.092213 [ 2819855 ] {} <Fatal> BaseDaemon: (version 25.8.16.20001.altinityantalya, build id: 3038DF0907550E746F1D3AE5782185C910FA9621, git hash: d0067516968b65e97dde5438b400226df32be1a6) (from thread 2819804) (no query) Received signal Segmentation fault (11)
2026.03.10 17:30:17.092215 [ 2819855 ] {} <Fatal> BaseDaemon: Address: 0x3e8002b0b9e. Access: read. Unknown si_code.
2026.03.10 17:30:17.092218 [ 2819855 ] {} <Fatal> BaseDaemon: Stack trace: 0x0000737097a98d72 0x0000737097a9b7ed 0x00005b2cf902bf4f 0x00005b2cec6236cb 0x00005b2ce88a7b0a 0x00005b2cf8492666 0x00005b2ce888f4b0 0x00005b2ce888ca48 0x00005b2ce1aef61f 0x0000737097a2a1ca 0x0000737097a2a28b 0x00005b2ce1aee02e
2026.03.10 17:30:17.092686 [ 2819855 ] {} <Fatal> BaseDaemon: 3. __GI___futex_abstimed_wait_cancelable64 @ 0x0000000000098d72
2026.03.10 17:30:17.092705 [ 2819855 ] {} <Fatal> BaseDaemon: 4. __GI___pthread_cond_wait @ 0x000000000009b7ed
2026.03.10 17:30:17.096903 [ 2819855 ] {} <Fatal> BaseDaemon: 5.0. inlined from ./contrib/llvm-project/libcxx/include/__thread/support/pthread.h:122: std::__libcpp_condvar_wait[abi:ne190107](pthread_cond_t*, pthread_mutex_t*)
2026.03.10 17:30:17.096912 [ 2819855 ] {} <Fatal> BaseDaemon: 5. ./ci/tmp/build/./contrib/llvm-project/libcxx/src/condition_variable.cpp:30: std::condition_variable::wait(std::unique_lock<std::mutex>&) @ 0x00000000207b6f4f
2026.03.10 17:30:17.109935 [ 2819855 ] {} <Fatal> BaseDaemon: 6.0. inlined from ./contrib/llvm-project/libcxx/include/__condition_variable/condition_variable.h:147: void std::condition_variable::wait<BaseDaemon::waitForTerminationRequest()::$_0>(std::unique_lock<std::mutex>&, BaseDaemon::waitForTerminationRequest()::$_0)
2026.03.10 17:30:17.109942 [ 2819855 ] {} <Fatal> BaseDaemon: 6. ./ci/tmp/build/./src/Daemon/BaseDaemon.cpp:535: BaseDaemon::waitForTerminationRequest() @ 0x0000000013dae6cb
2026.03.10 17:30:17.130590 [ 2819855 ] {} <Fatal> BaseDaemon: 7. ./ci/tmp/build/./programs/server/Server.cpp:2878: DB::Server::main(std::vector<String, std::allocator<String>> const&) @ 0x0000000010032b0a
2026.03.10 17:30:17.134707 [ 2819855 ] {} <Fatal> BaseDaemon: 8. ./ci/tmp/build/./base/poco/Util/src/Application.cpp:315: Poco::Util::Application::run() @ 0x000000001fc1d666
2026.03.10 17:30:17.164842 [ 2819855 ] {} <Fatal> BaseDaemon: 9. ./ci/tmp/build/./programs/server/Server.cpp:637: DB::Server::run() @ 0x000000001001a4b0
2026.03.10 17:30:17.193289 [ 2819855 ] {} <Fatal> BaseDaemon: 10. ./ci/tmp/build/./programs/server/Server.cpp:424: mainEntryClickHouseServer(int, char**) @ 0x0000000010017a48
2026.03.10 17:30:17.195541 [ 2819855 ] {} <Fatal> BaseDaemon: 11. ./ci/tmp/build/./programs/main.cpp:381: main @ 0x000000000927a61f
2026.03.10 17:30:17.195551 [ 2819855 ] {} <Fatal> BaseDaemon: 12. __libc_start_call_main @ 0x000000000002a1ca
2026.03.10 17:30:17.195553 [ 2819855 ] {} <Fatal> BaseDaemon: 13. __libc_start_main_alias_2 @ 0x000000000002a28b
2026.03.10 17:30:17.232815 [ 2819855 ] {} <Fatal> BaseDaemon: 14. _start @ 0x000000000927902e
2026.03.10 17:30:17.232823 [ 2819855 ] {} <Fatal> BaseDaemon: Integrity check of the executable skipped because the reference checksum could not be read.
2026.03.10 17:30:17.232833 [ 2819855 ] {} <Debug> CrashWriter: Not sending crash report (crash reporting is disabled)
fish: Job 1, './clickhouse server' terminated by signal SIGSEGV (Address boundary error)

Note: No BAD_ARGUMENTS exception appears in the logs, confirming the fix prevents the error that occurred before PR #1438.

Comparison with PR #1438

• PR Antalya 25.8 - Skip crash report send path when disabled #1438 (Option A): Prevented exception but provided no logging when crashes occurred with reporting disabled
• PR Antalya 25.8 - Fix CrashWriter to check empty endpoint before sending crash report #1508 (Option B): Prevents exception AND provides informative logging for better observability

The fix successfully resolves #1437 while improving logging behavior.

[Enmk]

LGTM