gh-131338: Disable computed stack limit checks on non-glibc linux (#134336)

Co-authored-by: Kumar Aditya <[email protected]>
Co-authored-by: Victor Stinner <[email protected]>

Author: 3 people

Misc/NEWS.d/next/Core_and_Builtins/2025-07-25-22-31-52.gh-issue-131338.zJDCMp.rst

@@ -0,0 +1,2 @@
+Disable computed stack limit checks on non-glibc linux platforms to fix
+crashes on deep recursion.

Python/ceval.c

@@ -452,7 +452,11 @@ _Py_InitializeRecursionLimits(PyThreadState *tstate)
     _tstate->c_stack_soft_limit = _tstate->c_stack_hard_limit + _PyOS_STACK_MARGIN_BYTES;
 #else
     uintptr_t here_addr = _Py_get_machine_stack_pointer();
-#  if defined(HAVE_PTHREAD_GETATTR_NP) && !defined(_AIX) && !defined(__NetBSD__)
+/// XXX musl supports HAVE_PTHRED_GETATTR_NP, but the resulting stack size
+/// (on alpine at least) is much smaller than expected and imposes undue limits
+/// compared to the old stack size estimation.  (We assume musl is not glibc.)
+#  if defined(HAVE_PTHREAD_GETATTR_NP) && !defined(_AIX) && \
+        !defined(__NetBSD__) && (defined(__GLIBC__) || !defined(__linux__))
     size_t stack_size, guard_size;
     void *stack_addr;
     pthread_attr_t attr;