Remove support for non ISO C99 vararg support

We require ISO C99 as minimum support for our source code and all compilers
should support the ISO C99 macros. Especially gcc does not need
the gcc extensions anymore. Also MSVC has support for it (as defined
in the config-msvc.h but also double checked)

LCLINT seems to be a C analyzer that history has forgotten about. I could
only find https://splint.org/release1.3.html and an similarly old research
paper.

Patch V2: Also remove AX_ macros from configure.ac

Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Acked-by: Steffan Karger <steffan.karger@foxcrypto.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20210328142038.8826-2-arne@rfc2549.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg21883.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

diff --git a/config-msvc.h b/config-msvc.h
index 0260927ce117db0f2b00f54d3a4c4f4d065ba067..4db9efae2fc983996c6209aa3ab14f68267f8cbe 100644 (file)
--- a/config-msvc.h
+++ b/config-msvc.h
@@ -47,7 +47,6 @@
 #define HAVE_ACCESS 1
 #define HAVE_CHDIR 1
 #define HAVE_CHSIZE 1
-#define HAVE_CPP_VARARG_MACRO_ISO 1
 #define HAVE_CTIME 1
 #define HAVE_EVP_CIPHER_CTX_SET_KEY_LENGTH 1
 #define HAVE_IN_PKTINFO 1

diff --git a/configure.ac b/configure.ac
index c17266a0a5c40bae4a3d64ff87e7655b7532754c..8e31dcb29c4c44115cdcb76ba90899665dad572c 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -418,8 +418,6 @@ AC_TYPE_UINT16_T
 AC_TYPE_UINT32_T
 AC_TYPE_UINT64_T
 AC_TYPE_SIGNAL
-AX_CPP_VARARG_MACRO_ISO
-AX_CPP_VARARG_MACRO_GCC
 AX_TYPE_SOCKLEN_T
 AC_CHECK_SIZEOF([unsigned int])
 AC_CHECK_SIZEOF([unsigned long])

diff --git a/m4/ax_varargs.m4 b/m4/ax_varargs.m4
deleted file mode 100644 (file)
index c295d21..0000000
--- a/m4/ax_varargs.m4
+++ /dev/null
@@ -1,77 +0,0 @@
-dnl @synopsis AX_CPP_VARARG_MACRO_GCC
-dnl
-dnl Test if the preprocessor understands GNU GCC-style vararg macros.
-dnl If it does, defines HAVE_CPP_VARARG_MACRO_GCC to 1.
-dnl
-dnl @version
-dnl @author James Yonan <jim@yonan.net>, Matthias Andree <matthias.andree@web.de>
-AC_DEFUN([AX_CPP_VARARG_MACRO_GCC], [dnl
-       AS_VAR_PUSHDEF([VAR], [ax_cv_cpp_vararg_macro_gcc])dnl
-       AC_CACHE_CHECK(
-               [for GNU GCC vararg macro support],
-               [VAR],
-               [AC_COMPILE_IFELSE(
-                       [AC_LANG_PROGRAM(
-                               [[
-#define macro(a, b...) func(a, b)
-int func(int a, int b, int c);
-                               ]],
-                               [[
-int i = macro(1, 2, 3);
-                               ]]
-                       )],
-                       [VAR=yes],
-                       [VAR=no]
-               )]
-       )dnl
-
-       AS_VAR_IF(
-               [VAR],
-               [yes],
-               [AC_DEFINE(
-                       [HAVE_CPP_VARARG_MACRO_GCC],
-                       [1], 
-                       [Define to 1 if your compiler supports GNU GCC-style variadic macros]
-               )]
-       )dnl
-       AS_VAR_POPDEF([VAR])dnl
-])
-
-dnl @synopsis AX_CPP_VARARG_MACRO_ISO
-dnl
-dnl Test if the preprocessor understands ISO C 1999 vararg macros.
-dnl If it does, defines HAVE_CPP_VARARG_MACRO_ISO to 1.
-dnl
-dnl @version
-dnl @author James Yonan <jim@yonan.net>, Matthias Andree <matthias.andree@web.de>
-AC_DEFUN([AX_CPP_VARARG_MACRO_ISO], [dnl
-       AS_VAR_PUSHDEF([VAR],[ax_cv_cpp_vararg_macro_iso])dnl
-       AC_CACHE_CHECK(
-               [for ISO C 1999 vararg macro support],
-               [VAR],
-               [AC_COMPILE_IFELSE(
-                       [AC_LANG_PROGRAM(
-                               [[
-#define macro(a, ...) func(a, __VA_ARGS__)
-int func(int a, int b, int c);
-                               ]],
-                               [[
-int i = macro(1, 2, 3);
-                               ]]
-                       )],
-                       [VAR=yes],
-                       [VAR=no]
-               )]
-       )dnl
-
-       AS_VAR_IF(
-               [VAR],
-               [yes],
-               [AC_DEFINE(
-                       [HAVE_CPP_VARARG_MACRO_ISO],
-                       [1], 
-                       [Define to 1 if your compiler supports ISO C99 variadic macros]
-               )]
-       )dnl
-       AS_VAR_POPDEF([VAR])dnl
-])

diff --git a/src/openvpn/error.c b/src/openvpn/error.c
index 0ecbfc33072de7a7ff1645b32287e5184e096039..e6f7ff0ff5a46c619e29b08d67cc4e32df444c8a 100644 (file)
--- a/src/openvpn/error.c
+++ b/src/openvpn/error.c
@@ -236,26 +236,22 @@ x_msg_va(const unsigned int flags, const char *format, va_list arglist)
 
     void usage_small(void);
 
-#ifndef HAVE_VARARG_MACROS
     /* the macro has checked this otherwise */
     if (!msg_test(flags))
     {
         return;
     }
-#endif
 
     e = openvpn_errno();
 
     /*
      * Apply muting filter.
      */
-#ifndef HAVE_VARARG_MACROS
     /* the macro has checked this otherwise */
     if (!dont_mute(flags))
     {
         return;
     }
-#endif
 
     gc_init(&gc);
 

diff --git a/src/openvpn/error.h b/src/openvpn/error.h
index eaedf172c514398fb242cd2bd4a90f425d811394..1a552165488ff184819c4dd1f5369fda1037aed6 100644 (file)
--- a/src/openvpn/error.h
+++ b/src/openvpn/error.h
@@ -146,33 +146,12 @@ bool dont_mute(unsigned int flags);
 /* Macro to ensure (and teach static analysis tools) we exit on fatal errors */
 #define EXIT_FATAL(flags) do { if ((flags) & M_FATAL) {_exit(1);}} while (false)
 
-#if defined(HAVE_CPP_VARARG_MACRO_ISO) && !defined(__LCLINT__)
-#define HAVE_VARARG_MACROS
 #define msg(flags, ...) do { if (msg_test(flags)) {x_msg((flags), __VA_ARGS__);} EXIT_FATAL(flags); } while (false)
 #ifdef ENABLE_DEBUG
 #define dmsg(flags, ...) do { if (msg_test(flags)) {x_msg((flags), __VA_ARGS__);} EXIT_FATAL(flags); } while (false)
 #else
 #define dmsg(flags, ...)
 #endif
-#elif defined(HAVE_CPP_VARARG_MACRO_GCC) && !defined(__LCLINT__)
-#define HAVE_VARARG_MACROS
-#define msg(flags, args ...) do { if (msg_test(flags)) {x_msg((flags), args);} EXIT_FATAL(flags); } while (false)
-#ifdef ENABLE_DEBUG
-#define dmsg(flags, args ...) do { if (msg_test(flags)) {x_msg((flags), args);} EXIT_FATAL(flags); } while (false)
-#else
-#define dmsg(flags, args ...)
-#endif
-#else  /* if defined(HAVE_CPP_VARARG_MACRO_ISO) && !defined(__LCLINT__) */
-#if !PEDANTIC
-#ifdef _MSC_VER
-#pragma message("this compiler appears to lack vararg macros which will cause a significant degradation in efficiency")
-#else
-#warning this compiler appears to lack vararg macros which will cause a significant degradation in efficiency (you can ignore this warning if you are using LCLINT)
-#endif
-#endif
-#define msg x_msg
-#define dmsg x_msg
-#endif /* if defined(HAVE_CPP_VARARG_MACRO_ISO) && !defined(__LCLINT__) */
 
 void x_msg(const unsigned int flags, const char *format, ...)
 #ifdef __GNUC__

diff --git a/src/tapctl/error.h b/src/tapctl/error.h
index 924cbbe89f515b11d8c830ec57f8d9a30c7ce0db..cea50ba5218bb74ffe527d2dd8941640f5d53cb0 100644 (file)
--- a/src/tapctl/error.h
+++ b/src/tapctl/error.h
@@ -67,7 +67,6 @@ bool dont_mute(unsigned int flags);
 #endif
 #define EXIT_FATAL(flags) do { if ((flags) & M_FATAL) {_exit(1);}} while (false)
 
-#define HAVE_VARARG_MACROS
 #define msg(flags, ...) do { if (msg_test(flags)) {x_msg((flags), __VA_ARGS__);} EXIT_FATAL(flags); } while (false)
 #ifdef ENABLE_DEBUG
 #define dmsg(flags, ...) do { if (msg_test(flags)) {x_msg((flags), __VA_ARGS__);} EXIT_FATAL(flags); } while (false)