From 33eda4304209d56fc8c723807aff1a09221f16d2 Mon Sep 17 00:00:00 2001
From: "H. Peter Anvin" <hpa@zytor.com>
Date: Mon, 11 Aug 2025 18:54:17 -0700
Subject: [PATCH] autoconf: update m4 macros and config/unconfig.h

(Does unconfig.h really need to be in the git tree?)

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
---
 autoconf/m4/pa_add_flags.m4         |  9 ++++-----
 autoconf/m4/pa_common_attributes.m4 |  1 -
 autoconf/m4/pa_option_debug.m4      |  2 --
 autoconf/m4/pa_option_profiling.m4  |  5 +----
 autoconf/m4/pa_variadic_macros.m4   | 24 ++++++++++++++++++++----
 config/unconfig.h                   | 16 ----------------
 6 files changed, 25 insertions(+), 32 deletions(-)

diff --git a/autoconf/m4/pa_add_flags.m4 b/autoconf/m4/pa_add_flags.m4
index c7fb7656..23f96f12 100644
--- a/autoconf/m4/pa_add_flags.m4
+++ b/autoconf/m4/pa_add_flags.m4
@@ -1,10 +1,9 @@
 dnl --------------------------------------------------------------------------
-dnl PA_ADD_FLAGS(flagvar, flags [, real-flags [, success [, failure]]])
+dnl PA_ADD_FLAGS(flagvar, flags)
 dnl
-dnl  Add [real-flags] (default [flags]) to the variable [flagvar] if
-dnl  and only if [flags] are accepted by all languages affected by
-dnl  [flagvar], if those languages have been previously seen in the
-dnl  script.
+dnl  Add [flags] to the variable [flagvar] if and only if it is accepted
+dnl  by all languages affected by [flagvar], if those languages have
+dnl  been previously seen in the script.
 dnl --------------------------------------------------------------------------
 AC_DEFUN([PA_ADD_FLAGS],
 [
diff --git a/autoconf/m4/pa_common_attributes.m4 b/autoconf/m4/pa_common_attributes.m4
index 0594f3e1..8b8dc9e3 100644
--- a/autoconf/m4/pa_common_attributes.m4
+++ b/autoconf/m4/pa_common_attributes.m4
@@ -15,6 +15,5 @@ AC_DEFUN([PA_COMMON_ATTRIBUTES],
  PA_FUNC_ATTRIBUTE(const)
  PA_FUNC_ATTRIBUTE(pure)
  PA_FUNC_ATTRIBUTE(cold,,,,,unlikely_func)
- PA_FUNC_ATTRIBUTE(used)
  PA_FUNC_ATTRIBUTE(unused)
  PA_FUNC_ATTRIBUTE_ERROR])
diff --git a/autoconf/m4/pa_option_debug.m4 b/autoconf/m4/pa_option_debug.m4
index 0c9dd372..ae7d9db8 100644
--- a/autoconf/m4/pa_option_debug.m4
+++ b/autoconf/m4/pa_option_debug.m4
@@ -9,7 +9,5 @@ AC_DEFUN([PA_OPTION_DEBUG],
  [PA_ADD_LANGFLAGS([-g3])], [PA_ADD_LANGFLAGS([-ggdb3 -g3])])
  PA_ARG_ENABLED([debug], [optimize for debugging],
  [PA_ADD_LANGFLAGS([-Og -O0])
-  AC_DEFINE([WITH_DEBUG], 1,
-  [Define to 1 to include code specifically indended to help debugging.])
   $1],
  [$2])])
diff --git a/autoconf/m4/pa_option_profiling.m4 b/autoconf/m4/pa_option_profiling.m4
index fb409e42..39a3f6cf 100644
--- a/autoconf/m4/pa_option_profiling.m4
+++ b/autoconf/m4/pa_option_profiling.m4
@@ -5,7 +5,4 @@ dnl Try to enable profiling if --enable-profiling is set.
 dnl --------------------------------------------------------------------------
 AC_DEFUN([PA_OPTION_PROFILING],
 [PA_ARG_ENABLED([profiling], [compile with profiling (-pg option)],
-[PA_ADD_LANGFLAGS([-pg])
- AC_DEFINE([WITH_PROFILING], 1,
-  [Define to 1 to include code specifically indended to help profiling.])
-])])
+[PA_ADD_LANGFLAGS([-pg])])])
diff --git a/autoconf/m4/pa_variadic_macros.m4 b/autoconf/m4/pa_variadic_macros.m4
index a2372ce2..3c7b1c09 100644
--- a/autoconf/m4/pa_variadic_macros.m4
+++ b/autoconf/m4/pa_variadic_macros.m4
@@ -14,7 +14,23 @@ int main(void)
 	return 0;
 }
 ])],[pa_cv_variadic_macros=yes],[pa_cv_variadic_macros=no])])
-	AS_IF([test "x$pa_cv_variadic_macros" = xyes],
-	[AC_DEFINE([HAVE_VARIADIC_MACROS], 1,
-[define to 1 if your compiler supports C99 __VA_ARGS__ variadic macros.])])
-])
+AS_IF([test "x$pa_cv_variadic_macros" = xyes],
+ [AC_DEFINE([HAVE_VARIADIC_MACROS], 1,
+  [define to 1 if your compiler supports C99 __VA_ARGS__ variadic macros.])
+  AC_CACHE_CHECK([if $CC supports varadic macro comma dropping],
+  [pa_cv_varadic_macros_comma_hack],
+  [AC_LINK_IFELSE([AC_LANG_SOURCE([
+AC_INCLUDES_DEFAULT
+#define myprintf(f, ...) printf(f, ## __VA_ARGS__)
+int main(void)
+{
+	myprintf("hello");
+	return 0;
+}
+])])],
+[pa_cv_varadic_macros_comma_hack=yes],
+[pa_cv_varadic_macros_comma_hack=no])
+AS_IF([test "x$pa_cv_varadic_macros_comma_hack" = xyes],
+[AC_DEFINE([HAVE_VARADIC_MACROS_COMMA_HACK], 1,
+ [define to 1 if your compiler supports the , ## __VA_ARGS__ hack.])])
+])])
diff --git a/config/unconfig.h b/config/unconfig.h
index 3713ecfa..3afcb206 100644
--- a/config/unconfig.h
+++ b/config/unconfig.h
@@ -107,22 +107,6 @@
 # endif
 #endif
 
-#ifndef used_func
-# ifdef HAVE_FUNC_ATTRIBUTE_USED
-#  define used_func ATTRIBUTE(used)
-# else
-#  define used_func
-# endif
-#endif
-
-#ifndef used_func_ptr
-# ifdef HAVE_FUNC_PTR_ATTRIBUTE_USED
-#  define used_func_ptr ATTRIBUTE(used)
-# else
-#  define used_func_ptr
-# endif
-#endif
-
 #ifndef unused_func
 # ifdef HAVE_FUNC_ATTRIBUTE_UNUSED
 #  define unused_func ATTRIBUTE(unused)