1 files changed, 10 insertions, 2 deletions

diff --git a/gl/m4/vsnprintf.m4 b/gl/m4/vsnprintf.m4
index 4900764e..5f5375e6 100644
--- a/gl/m4/vsnprintf.m4
+++ b/gl/m4/vsnprintf.m4
@@ -1,5 +1,5 @@
-# vsnprintf.m4 serial 6
-dnl Copyright (C) 2002-2004, 2007-2013 Free Software Foundation, Inc.
+# vsnprintf.m4 serial 7
+dnl Copyright (C) 2002-2004, 2007-2021 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -46,6 +46,14 @@ AC_DEFUN([gl_REPLACE_VSNPRINTF],
   AC_LIBOBJ([vsnprintf])
   if test $ac_cv_func_vsnprintf = yes; then
     REPLACE_VSNPRINTF=1
+  else
+    AC_CHECK_DECLS_ONCE([vsnprintf])
+    if test $ac_cv_have_decl_vsnprintf = yes; then
+      dnl If the function is declared but does not appear to exist, it may be
+      dnl defined as an inline function. In order to avoid a conflict, we have
+      dnl to define rpl_vsnprintf, not vsnprintf.
+      REPLACE_VSNPRINTF=1
+    fi
   fi
   gl_PREREQ_VSNPRINTF
 ])