github-actions[bot] commented on code in PR #69231:
URL: https://github.com/apache/doris/pull/69231#discussion_r4306732383


##########
thirdparty/vars.sh:
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@@ -105,10 +105,10 @@ SNAPPY_SOURCE=snappy-1.2.1
 SNAPPY_MD5SUM="dd6f9b667e69491e1dbf7419bdf68823"
 
 # gperftools
-GPERFTOOLS_DOWNLOAD="https://github.com/gperftools/gperftools/releases/download/gperftools-2.10/gperftools-2.10.tar.gz";
-GPERFTOOLS_NAME=gperftools-2.10.tar.gz
-GPERFTOOLS_SOURCE=gperftools-2.10
-GPERFTOOLS_MD5SUM="62bf6c76ba855ed580de5e139bd2a483"
+GPERFTOOLS_DOWNLOAD="https://github.com/gperftools/gperftools/releases/download/gperftools-2.18.1/gperftools-2.18.1.tar.gz";

Review Comment:
   [P1] Preserve signal-safe unwinding for Linux ARM64 profiles
   
   The existing `build_gperftools` flags are `--disable-libunwind 
--enable-frame-pointers`, but [2.18.1's 
selector](https://github.com/gperftools/gperftools/blob/gperftools-2.18.1/src/stacktrace.cc#L197-L271)
 honors forced frame pointers only on x86, so ARM64 now chooses libgcc's 
`_Unwind_Backtrace` instead of 2.10's `generic_fp`. This affects the default 
jemalloc build too because `libprofiler.a` is always linked. On a supported GCC 
11/glibc 2.17 build, `/pprof/profile` can now deadlock: thread A holds the 
loader lock during ordinary exception unwinding; SIGPROF on B holds gperftools' 
`signal_lock_` and calls `_Unwind_Backtrace` -> 
[`dl_iterate_phdr`](https://github.com/gcc-mirror/gcc/blob/releases/gcc-11.5.0/libgcc/unwind-dw2-fde-dip.c#L470),
 waiting for A; the next profiling tick on A waits for `signal_lock_`. The CPU 
profiler does not enter `ScopedPHDRCacheRead`, and Doris's separate 
GNU-libunwind hook does not protect libgcc. Please retain `generic_fp` on Linux 
ARM64, or integra
 te a signal-safe unwinder along with this upgrade.



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