Do not use pthread_{get,set}name_np() if we don't have GLIBC.

[vkalintiris]

Summary

pthread_{get,set}name_np() are nonstandard GNU extensions which are
included only when _GNU_SOURCE is defined under GLIBC.

[brucem]

This would break this feature on Android, no?

[labath]

source/Host/linux/HostThreadLinux.cpp

44 ↗

(On Diff #35248)

While the pthread functions is a glibc extension, the presence of the comm file under /proc definitely does not depend on the C library used. This does not need to be ifdef-ed out.

If you're feeling adventurous, you could reimplement SetName to write to this file and have this functionality regardless of the shared library. If not then ifdef-out the first part only.

[vkalintiris]

Addressed reviewers comments. With the updated version we shouldn't break Android.

[labath]

looks good

lldb/trunk/source/Host/linux/HostThreadLinux.cpp

 HostThreadLinux::HostThreadLinux(lldb::thread_t thread)
     : HostThreadPosix(thread)
 {
 }
 
 void
 HostThreadLinux::SetName(lldb::thread_t thread, llvm::StringRef name)
 {
+#if (defined(__GLIBC__) && defined(_GNU_SOURCE)) || defined(__ANDROID__)
     ::pthread_setname_np(thread, name.data());
+#else
+    (void) thread;
+    (void) name;
+#endif
 }
 
 void
 HostThreadLinux::GetName(lldb::thread_t thread, llvm::SmallVectorImpl<char> &name)
 {
     // Read /proc/$TID/comm file.
     lldb::DataBufferSP buf_sp = process_linux::ProcFileReader::ReadIntoDataBuffer(thread, "comm");
     const char *comm_str = (const char *)buf_sp->GetBytes();
     const char *cr_str = ::strchr(comm_str, '\n');
     size_t length = cr_str ? (cr_str - comm_str) : strlen(comm_str);
 
     name.clear();
     name.append(comm_str, comm_str + length);
 }