From dfaae947da7371d955b071095e4e6f42978a417f Mon Sep 17 00:00:00 2001
From: Sergey B Kirpichev <skirpichev@gmail.com>
Date: Fri, 13 Sep 2024 09:50:16 +0300
Subject: [PATCH] Add signal handler to catch SIGFPE on the GMP 6.3+

Since 6.3.0 some memory errors in mpz/realloc.c trigger
SIGFPE exception.  I think it's an upstream bug: helpful
message should be emitted instead.

This patch install SIGFPE handler, that does this.

Closes #497
---
 src/gmpy2.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/src/gmpy2.c b/src/gmpy2.c
index 89ae1cd2..0629e0ba 100644
--- a/src/gmpy2.c
+++ b/src/gmpy2.c
@@ -96,6 +96,7 @@
 #include <math.h>
 #include <float.h>
 #include <ctype.h>
+#include <signal.h>
 
 /*
  * we do have a dependence on Python's internals, specifically:
@@ -567,6 +568,23 @@ static struct PyModuleDef moduledef = {
         NULL
 };
 
+void
+gmp_abort_handler(int i)
+{
+    if (__GNU_MP_VERSION == 6 &&  __GNU_MP_VERSION_MINOR >= 3) {
+        if (gmp_errno & GMP_ERROR_DIVISION_BY_ZERO) {
+            printf("gmp: divide by zero\n");
+        }
+        else if (gmp_errno & GMP_ERROR_SQRT_OF_NEGATIVE) {
+            printf("gmp: root of negative\n");
+        }
+        else {
+            printf("gmp: out of memory\n");
+        }
+    }
+    abort();
+}
+
 PyMODINIT_FUNC PyInit_gmpy2(void)
 {
     PyObject *result = NULL;
@@ -947,5 +965,7 @@ PyMODINIT_FUNC PyInit_gmpy2(void)
         /* LCOV_EXCL_STOP */
     }
 
+    PyOS_setsig(SIGFPE, gmp_abort_handler);
+
     return gmpy_module;
 }