--- a/src/parser/snprintf.c
+++ b/src/parser/snprintf.c
@@ -403,17 +404,6 @@
  * Note: glibc declares this as returning "char *", but that would require
  * casting away const internally, so we don't follow that detail.
  */
-#ifndef HAVE_STRCHRNUL
-
-static inline const char *
-strchrnul(const char *s, int c)
-{
-	while (*s != '\0' && *s != c)
-		s++;
-	return s;
-}
-
-#else
 
 /*
  * glibc's <string.h> declares strchrnul only if _GNU_SOURCE is defined.
@@ -425,7 +415,6 @@
 extern char *strchrnul(const char *s, int c);
 #endif
 
-#endif							/* HAVE_STRCHRNUL */
 
 
 /*
@@ -767,9 +756,10 @@
 				break;
 			case 'm':
 				{
-					char		errbuf[PG_STRERROR_R_BUFLEN];
-					const char *errm = strerror_r(save_errno,
+					char		errbuf[256];
+					int ret = strerror_r(save_errno,
 												  errbuf, sizeof(errbuf));
+					const char *errm = (ret == 0) ? errbuf : "Unknown error";
 
 					dostr(errm, strlen(errm), target);
 				}