diff --unified --recursive --text mlucas_v19/src/Mlucas.c mlucas_v19-1/src/Mlucas.c
--- mlucas_v19/src/Mlucas.c	2020-11-28 13:49:49.478452597 -0500
+++ mlucas_v19-1/src/Mlucas.c	2020-11-28 13:49:07.820195013 -0500
@@ -100,7 +100,7 @@
 char in_line[STR_MAX_LEN];
 char *char_addr;
 int char_offset;
-FILE *fq;
+FILE *fp, *fq;
 
 /* File access mode is a 3-character string, with the last of these being a mandatory null terminator: */
 char FILE_ACCESS_MODE[3] = {'x','y','\0'};
Only in mlucas_v19/src: Mlucas.c~