From e63cc01c72a7af0eb1cf2e3ef621a0cc8be4e14a Mon Sep 17 00:00:00 2001
From: Matt Borland <matt@mattborland.com>
Date: Wed, 25 Jan 2023 20:28:53 -0800
Subject: [PATCH] BUG: special: Fix handling of `powm1` overflow errors
 (#17855)

---
 scipy/special/boost_special_functions.h | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/scipy/special/boost_special_functions.h b/scipy/special/boost_special_functions.h
index ae825e5de388..835ccb9af2b6 100644
--- a/scipy/special/boost_special_functions.h
+++ b/scipy/special/boost_special_functions.h
@@ -90,7 +90,12 @@ Real powm1_wrap(Real x, Real y)
         z = NAN;
     } catch (const std::overflow_error& e) {
         sf_error("powm1", SF_ERROR_OVERFLOW, NULL);
-        z = INFINITY;
+        if (x > 0) {
+            z = INFINITY;
+        }
+        else {
+            z = -INFINITY;
+        }
     } catch (const std::underflow_error& e) {
         sf_error("powm1", SF_ERROR_UNDERFLOW, NULL);
         z = 0;