diff -up ./abcm2ps-8.14.15/format.c.gnu23 ./abcm2ps-8.14.15/format.c
--- ./abcm2ps-8.14.15/format.c.gnu23	2024-01-08 02:15:18.000000000 -0500
+++ ./abcm2ps-8.14.15/format.c	2025-01-24 16:13:01.068045837 -0500
@@ -1158,13 +1158,13 @@ void interpret_fmt_line(char *w,		/* key
 		}
 		if (strcmp(w, "writehistory") == 0) {	/* compatibility */
 			struct SYMBOL *s;
-			int bool;
+			int ibool;
 			unsigned u;
 
-			bool = get_bool(p);
+			ibool = get_bool(p);
 			for (s = info['I' - 'A']; s != 0; s = s->next) {
 				u = s->text[0] - 'A';
-				if (bool)
+				if (ibool)
 					cfmt.fields[0] |= (1 << u);
 				else
 					cfmt.fields[0] &= ~(1 << u);
@@ -1215,7 +1215,7 @@ void interpret_fmt_line(char *w,		/* key
 			}
 			break;
 		case 1:	{			/* %%writefields */
-			int bool;
+			int ibool;
 			unsigned u;
 
 			q = p;
@@ -1223,7 +1223,7 @@ void interpret_fmt_line(char *w,		/* key
 				p++;
 			while (isspace((unsigned char) *p))
 				p++;
-			bool = get_bool(p);
+			ibool = get_bool(p);
 			while (*q != '\0' && !isspace((unsigned char) *q)) {
 				u = *q - 'A';
 				if (u < 26) {
@@ -1235,7 +1235,7 @@ void interpret_fmt_line(char *w,		/* key
 					else
 						break;	/*fixme: error */
 				}
-				if (bool)
+				if (ibool)
 					cfmt.fields[i] |= (1 << u);
 				else
 					cfmt.fields[i] &= ~(1 << u);