Add comment and NEWS for thread state cleanup fix

zainnadeem786 · zainnadeem786 · commit 9d47a7b82d22 · 2026-06-26T00:11:10.000+05:00
diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2026-06-26-00-06-29.gh-issue-151763.pX4fYq.rst b/Misc/NEWS.d/next/Core_and_Builtins/2026-06-26-00-06-29.gh-issue-151763.pX4fYq.rst
@@ -0,0 +1,2 @@
+Fixed a possible crash in free-threaded builds when interpreter creation fails
+due to memory allocation failure.
diff --git a/Python/pystate.c b/Python/pystate.c
@@ -1661,6 +1661,8 @@ new_threadstate(PyInterpreterState *interp, int whence)
     if (tstate == NULL) {
         return NULL;
     }
+    // Set the back-pointer before init_threadstate() so early cleanup can
+    // recognize the preallocated initial thread state after allocation failures.
     tstate->base.interp = interp;
 
 #ifdef Py_GIL_DISABLED

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	`+Fixed a possible crash in free-threaded builds when interpreter creation fails`
	`2`	`+due to memory allocation failure.`
Original file line number	Diff line number	Diff line change
`@@ -1661,6 +1661,8 @@ new_threadstate(PyInterpreterState *interp, int whence)`
`1661`	`1661`	`if (tstate == NULL) {`
`1662`	`1662`	`return NULL;`
`1663`	`1663`	`}`
	`1664`	`+ // Set the back-pointer before init_threadstate() so early cleanup can`
	`1665`	`+ // recognize the preallocated initial thread state after allocation failures.`
`1664`	`1666`	`tstate->base.interp = interp;`
`1665`	`1667`
`1666`	`1668`	`#ifdef Py_GIL_DISABLED`