diff --git a/compat/sig2str.c b/compat/sig2str.c
index 6c9cd3966..d698df1e1 100644
--- a/compat/sig2str.c
+++ b/compat/sig2str.c
@@ -37,6 +37,7 @@
 # include <strings.h>
 #endif /* HAVE_STRINGS_H */
 #include <signal.h>
+#include <unistd.h>
 
 #include "missing.h"
 
diff --git a/configure b/configure
index 7f0ecd9d3..06cb7a6e6 100755
--- a/configure
+++ b/configure
@@ -14901,8 +14901,8 @@ $as_echo "no" >&6; }
 
 $as_echo "#define NO_VARIADIC_MACROS 1" >>confdefs.h
 
- { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: Your C compiler doesn't support variadic macros, debugging support will be limited" >&5
-$as_echo "$as_me: WARNING: Your C compiler doesn't support variadic macros, debugging support will be limited" >&2;}
+ { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: Your C preprocessor doesn't support variadic macros, debugging support will be limited" >&5
+$as_echo "$as_me: WARNING: Your C preprocessor doesn't support variadic macros, debugging support will be limited" >&2;}
 fi
 rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
 
diff --git a/configure.ac b/configure.ac
index 682e25fbe..c9e3a6822 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2077,7 +2077,7 @@ AC_INCLUDES_DEFAULT
 ], [sudo_fprintf(stderr, "a %s", "test");])], [AC_MSG_RESULT([yes])],
 [AC_MSG_RESULT([no])
  AC_DEFINE([NO_VARIADIC_MACROS], [1], [Define if your C preprocessor does not support variadic macros.])
- AC_MSG_WARN([Your C compiler doesn't support variadic macros, debugging support will be limited])])
+ AC_MSG_WARN([Your C preprocessor doesn't support variadic macros, debugging support will be limited])])
 
 dnl
 dnl Program checks