[PATCH v2] win32: use _endthreadex to terminate threads, not ExitThread

From: Rose via GitGitGadget <gitgitgadget@gmail.com>
Date: Dec 25, 2022, 01:41 UTC
Message-ID: <pull.1414.v2.git.git.1671932510529.gitgitgadget@gmail.com>
In-Reply-To: <pull.1414.git.git.1671742750504.gitgitgadget@gmail.com>

From: Seija Kijin <doremylover123@gmail.com>

Because we use the C runtime and use _beginthreadex to create pthreads, pthread_exit MUST use _endthreadex.

Otherwise, according to Microsoft: "Failure to do so results in small memory leaks when the thread calls ExitThread."

Simply put, this is not the same as ExitThread.

Signed-off-by: Seija Kijin <doremylover123@gmail.com>
---
    win32: use _endthreadex to terminate threads, not ExitThread
    
    Because we use the C runtime and use _beginthread to create pthreads,
    pthread_exit MUST use _endthread.
    
    Otherwise, according to Microsoft: "Failure to do so results in small
    memory leaks when the thread calls ExitThread."
    
    Simply put, this is not the same as ExitThread.
    
    Signed-off-by: Seija Kijin doremylover123@gmail.com

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1414%2FAtariDreams%2Fsevere-bug-v2
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1414/AtariDreams/severe-bug-v2
Pull-Request: https://github.com/git/git/pull/1414

Range-diff vs v1:

 1:  78f9d54c304 ! 1:  3e8212fb9a7 win32: use _endthreadex to terminate threads, not ExitThread
     @@ Metadata
       ## Commit message ##
          win32: use _endthreadex to terminate threads, not ExitThread
      
     -    This is a pretty serious bug actually:
          Because we use the C runtime and
          use _beginthreadex to create pthreads,
          pthread_exit MUST use _endthreadex.

 compat/win32/pthread.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compat/win32/pthread.h b/compat/win32/pthread.h
index 737983d00ba..cc3221cb2c8 100644
--- a/compat/win32/pthread.h
+++ b/compat/win32/pthread.h
@@ -66,7 +66,7 @@ pthread_t pthread_self(void);
 
 static inline void NORETURN pthread_exit(void *ret)
 {
-	ExitThread((DWORD)(intptr_t)ret);
+	_endthreadex((unsigned)(uintptr_t)ret);
 }
 
 typedef DWORD pthread_key_t;

base-commit: 7c2ef319c52c4997256f5807564523dfd4acdfc7

-- 
gitgitgadget