diff --git a/macros.gnat-srpm b/macros.gnat-srpm
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+# GNAT_arches lists the architectures where GNAT is available in Fedora. Ada
+# packages won't build on other architectures until GNAT is bootstrapped for
+# them.
+%GNAT_arches %{ix86} x86_64 ia64 ppc ppc64 alpha