gh-141370: document undefined behavior of Py_ABS()

skirpichev · skirpichev · commit 790ccfbfbfc2 · 2025-11-12T04:57:55.000+03:00
diff --git a/Doc/c-api/intro.rst b/Doc/c-api/intro.rst
@@ -119,7 +119,8 @@ complete listing.
 
 .. c:macro:: Py_ABS(x)
 
-   Return the absolute value of ``x``.
+   Return the absolute value of ``x``.  If the result cannot be represented in
+   same type, the behavior is undefined.
 
    .. versionadded:: 3.3
 
