Description: clear errno before using it to check failure from atof()
 The atof() function is not guaranteed to clear errno on success, so if
 any earlier errors have been set prior to calling atof(), these will
 result in a spurious failure.  On armhf, glibc 2.31 now opportunistically
 calls a new syscall that may not be supported on older kernels (Linux 4.15),
 resulting in errno == ENOSYS:
 .
 syscall_0x193(0x5, 0xffb2b650, 0xf77b7000, 0, 0x5, 0xffb2b650) = -1 ENOSYS (Function not implemented)
 .
 Therefore we should clear errno before calling atof() to make sure any
 errors actually originate from this function.
Author: Steve Langasek <steve.langasek@ubuntu.com>
Last-Update: 2020-03-11
Bug-Debian: https://bugs.debian.org/953675

Index: clearcut-1.0.9/dmat.c
===================================================================
--- clearcut-1.0.9.orig/dmat.c
+++ clearcut-1.0.9/dmat.c
@@ -570,6 +570,7 @@
 	goto XIT_BAD;
       }
 
+      errno = 0;
       val = atof(token->buf);
       if(errno) {
 	fprintf(stderr, "Clearcut: Distance value out-of-range.\n");