--- libgit2-1.9.0/src/cli/opt.c.orig	2025-04-21 08:09:38.615653200 +0200
+++ libgit2-1.9.0/src/cli/opt.c	2025-04-21 08:09:48.209524900 +0200
@@ -19,7 +19,7 @@
 #include <limits.h>
 #include <assert.h>
 
-#if defined(__sun) || defined(__illumos__)
+#if defined(__sun) || defined(__illumos__) || defined(__CYGWIN__)
 # include <alloca.h>
 #endif