From: Guy Harris <guy@alum.mit.edu>
Date: Mon, 29 Jan 2018 08:57:02 +0000 (-0800)
Subject: Use check_symbol_exists for {v}snprintf().
X-Git-Tag: tcpdump-4.99-bp~1329
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/494c8096e0881e4f82440bc7b0b41b6969cd92b9

Use check_symbol_exists for {v}snprintf().

With MSVC 2015, stdio.h defines snprintf() and vsnprintf() as inline
functions, so you need to include stdio.h when testing for them -
check_function_exists() won't do it, you need check_symbol_exists().
---

diff --git a/CMakeLists.txt b/CMakeLists.txt
index c34d21bc..5cc87ded 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -203,8 +203,13 @@ endif(STDLIBS_HAVE_GETSERVENT)
 cmake_pop_check_state()
 
 check_function_exists(getopt_long HAVE_GETOPT_LONG)
-check_function_exists(vsnprintf HAVE_VSNPRINTF)
-check_function_exists(snprintf HAVE_SNPRINTF)
+#
+# With MSVC 2015, stdio.h defines snprintf() and vsnprintf() as inline
+# functions, so you need to include stdio.h when testing for them -
+# check_function_exists() won't do it, you need check_symbol_exists().
+#
+check_symbol_exists(vsnprintf stdio.h HAVE_VSNPRINTF)
+check_symbol_exists(snprintf stdio.h HAVE_SNPRINTF)
 check_function_exists(fork HAVE_FORK)
 check_function_exists(vfork HAVE_VFORK)
 check_function_exists(strftime HAVE_STRFTIME)