diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index dfd102a..f27ab56 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -791,6 +791,7 @@ int
 errmsg(const char *fmt,...)
 {
 	ErrorData  *edata = &errordata[errordata_stack_depth];
+	int			saved_errno = errno;	/* Not clobber errno. */
 	MemoryContext oldcontext;
 
 	recursion_depth++;
@@ -801,6 +802,7 @@ errmsg(const char *fmt,...)
 
 	MemoryContextSwitchTo(oldcontext);
 	recursion_depth--;
+	errno = saved_errno;
 	return 0;					/* return value does not matter */
 }