pythonGH-113655: Lower the C recursion limit for PPC64 and SPARC

Lower the C recursion limit for PPC64 and SPARC, as they use relatively
large stack frames that cause e.g. `test_descr` to hit a stack overflow.
According to quick testing, it seems that values around 8000 are max
for PPC64 (ELFv1 ABI) and 7000 for SPARC64.  To keep things safe, let's
use 5000 for PPC64 and 4000 for SPARC.

Co-authored-by: Sam James <[email protected]>

Author: mgorny

Include/cpython/pystate.h

@@ -218,9 +218,15 @@ struct _ts {
 #  define Py_C_RECURSION_LIMIT 3000
 #elif defined(_Py_ADDRESS_SANITIZER)
 #  define Py_C_RECURSION_LIMIT 4000
+#elif defined(__sparc__)
+   // test_descr crashed on sparc64 with >7000 but let's keep a margin of error.
+#  define Py_C_RECURSION_LIMIT 4000
 #elif defined(__wasi__)
    // Based on wasmtime 16.
 #  define Py_C_RECURSION_LIMIT 5000
+#elif defined(__powerpc64__)
+   // test_descr crashed on ppc64 with >8000 but let's keep a margin of error.
+#  define Py_C_RECURSION_LIMIT 5000
 #else
    // This value is duplicated in Lib/test/support/__init__.py
 #  define Py_C_RECURSION_LIMIT 10000