freebsd-ports/math/octave/files/patch-libgnu_math.in.h

--- libgnu/math.in.h.orig	2022-11-02 18:19:56 UTC
+++ libgnu/math.in.h
@@ -15,7 +15,7 @@
    You should have received a copy of the GNU Lesser General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
 
-#ifndef _@GUARD_PREFIX@_MATH_H
+#if 1
 
 #if __GNUC__ >= 3
 @PRAGMA_SYSTEM_HEADER@