5 files changed, 108 insertions, 30 deletions
diff --git a/lib/autoconf/functions.m4 b/lib/autoconf/functions.m4
index 44730096..645a7c60 100644
--- a/lib/autoconf/functions.m4
+++ b/lib/autoconf/functions.m4
@@ -78,6 +78,34 @@ m4_define([_AH_CHECK_FUNC],
 [AH_TEMPLATE(AS_TR_CPP([HAVE_$1]),
   [Define to 1 if you have the `$1' function.])])
 
+# _AC_CHECK_FUNCS_ONE_U(FUNCTION)
+# -------------------------------
+# Perform the actions that need to be performed unconditionally
+# for every FUNCTION that *could* be checked for by AC_CHECK_FUNCS.
+m4_define([_AC_CHECK_FUNCS_ONE_U],
+[AS_LITERAL_WORD_IF([$1],
+  [_AH_CHECK_FUNC([$1])],
+  [AC_DIAGNOSE([syntax], [AC_CHECK_FUNCS($1): you should use literals])])])
+
+# _AC_CHECK_FUNCS_ONE_S(FUNCTION)
+# -------------------------------
+# If FUNCTION exists, define HAVE_FUNCTION.  FUNCTION must be literal.
+# Used by AC_CHECK_FUNCS for its simplest case, when its FUNCTION list
+# is fully literal and no optional actions were supplied.
+m4_define([_AC_CHECK_FUNCS_ONE_S],
+[_AH_CHECK_FUNC([$1])]dnl
+[AC_CHECK_FUNC([$1],
+  [AC_DEFINE(AS_TR_CPP([HAVE_$1]))])])
+
+# _AC_CHECK_FUNCS_ONE_C(FUNCTION, [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
+# -------------------------------------------------------------------------
+# If FUNCTION exists, define HAVE_FUNCTION and execute ACTION-IF-FOUND.
+# Otherwise execute ACTION-IF-NOT-FOUND.  FUNCTION can be a shell variable.
+# Used by AC_CHECK_FUNCS for complex cases.
+m4_define([_AC_CHECK_FUNCS_ONE_C],
+[AC_CHECK_FUNC([$1],
+  [AC_DEFINE_UNQUOTED(AS_TR_CPP([HAVE_]$1)) $2],
+  [$3])])
 
 # AC_CHECK_FUNCS(FUNCTION..., [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
 # ---------------------------------------------------------------------
@@ -87,17 +115,14 @@ m4_define([_AH_CHECK_FUNC],
 # available for each found function.  Either ACTION may include
 # `break' to stop the search.
 AC_DEFUN([AC_CHECK_FUNCS],
-[m4_map_args_w([$1], [_AH_CHECK_FUNC(], [)])]dnl
-[m4_if([$2$3]AS_LITERAL_IF([$1], [[yes]], [[no]]), [yes],
-       [m4_map_args_w([$1], [_$0(], [)])],
-       [AS_FOR([AC_func], [ac_func], [$1], [_$0(AC_func, [$2], [$3])])])dnl
-])# AC_CHECK_FUNCS
+[_$0(m4_validate_w([$1]), [$2], [$3])])
 
 m4_define([_AC_CHECK_FUNCS],
-[AC_CHECK_FUNC([$1],
-	       [AC_DEFINE_UNQUOTED(AS_TR_CPP([HAVE_]$1)) $2],
-	       [$3])dnl
-])
+[m4_if([$2$3]AS_LITERAL_IF([$1], [[yes]], [[no]]), [yes],
+  [m4_map_args_w([$1], [_AC_CHECK_FUNCS_ONE_S(], [)])],
+  [m4_map_args_w([$1], [_AC_CHECK_FUNCS_ONE_U(], [)])]
+  [AS_FOR([AC_func], [ac_func], [$1],
+    [_AC_CHECK_FUNCS_ONE_C(AC_func, [$2], [$3])])])])
 
 
 # _AC_CHECK_FUNC_ONCE(FUNCTION)
@@ -114,7 +139,7 @@ m4_define([_AC_CHECK_FUNC_ONCE],
 # Add each whitespace-separated name in FUNCTION to the list of functions
 # to check once.
 AC_DEFUN([AC_CHECK_FUNCS_ONCE],
-[m4_map_args_w([$1], [_AC_CHECK_FUNC_ONCE(], [)])])
+[m4_map_args_w(m4_validate_w([$1]), [_AC_CHECK_FUNC_ONCE(], [)])])
 
 # _AC_FUNCS_EXPANSION(LANG)
 # -------------------------
@@ -177,7 +202,7 @@ m4_define([_AC_REPLACE_FUNC_NL],
 # equivalent of AC_CHECK_FUNC, then call AC_LIBOBJ if the function
 # was not found.
 AC_DEFUN([AC_REPLACE_FUNCS],
-[_$0(m4_flatten([$1]))])
+[_$0(m4_validate_w([$1]))])
 
 m4_define([_AC_REPLACE_FUNCS],
 [AS_LITERAL_IF([$1],
diff --git a/lib/autoconf/general.m4 b/lib/autoconf/general.m4
index e80f7eb0..e725d88c 100644
--- a/lib/autoconf/general.m4
+++ b/lib/autoconf/general.m4
@@ -1791,7 +1791,8 @@ m4_define([_AC_CONFIG_MACRO_DIRS],
 # If no directory has been traced yet, then this macro also triggers
 # a trace of AC_CONFIG_MACRO_DIR on the first directory.
 AC_DEFUN([AC_CONFIG_MACRO_DIRS],
-[m4_map_args_w([$1], [_$0(_$0_USED()[$0], ], [)])])
+[m4_map_args_w(m4_validate_w([$1]),
+  [_$0(_$0_USED()[$0], ], [)])])
 
 # AC_CONFIG_MACRO_DIR(DIR)
 # ------------------------
@@ -2879,7 +2880,8 @@ m4_define([_AC_CHECK_FILES],
 # ACTION-IF-FOUND or ACTION-IF-NOT-FOUND.  For files that exist, also
 # provide the preprocessor variable HAVE_FILE.
 AC_DEFUN([AC_CHECK_FILES],
-[m4_map_args_w([$1], [AC_CHECK_FILE(_$0(], [)[$2], [$3])])])
+[m4_map_args_w(m4_validate_w([$1]),
+  [AC_CHECK_FILE(_$0(], [)[$2], [$3])])])
 
 
 ## ------------------------------- ##
diff --git a/lib/autoconf/headers.m4 b/lib/autoconf/headers.m4
index be528261..ae8bf28f 100644
--- a/lib/autoconf/headers.m4
+++ b/lib/autoconf/headers.m4
@@ -173,6 +173,37 @@ m4_define([_AH_CHECK_HEADER],
 m4_define([AH_CHECK_HEADERS],
 [m4_foreach_w([AC_Header], [$1], [_AH_CHECK_HEADER(m4_defn([AC_Header]))])])
 
+# _AC_CHECK_HEADERS_ONE_U(HEADER-FILE)
+# -------------------------------
+# Perform the actions that need to be performed unconditionally
+# for every HEADER-FILE that *could* be checked for by AC_CHECK_HEADERS.
+m4_define([_AC_CHECK_HEADERS_ONE_U],
+[AS_LITERAL_WORD_IF([$1],
+  [_AH_CHECK_HEADER([$1])],
+  [AC_DIAGNOSE([syntax], [AC_CHECK_HEADERS($1): you should use literals])])])
+
+# _AC_CHECK_HEADERS_ONE_S(HEADER-FILE, [INCLUDES])
+# -------------------------------
+# If HEADER-FILE exists, define HAVE_HEADER_FILE.  HEADER-FILE must be literal.
+# Used by AC_CHECK_HEADERS for its simplest case, when its HEADER-FILE list
+# is fully literal and no optional actions were supplied.
+# INCLUDES is as for AC_CHECK_HEADER.
+m4_define([_AC_CHECK_HEADERS_ONE_S],
+[_AH_CHECK_HEADER([$1])]dnl
+[AC_CHECK_HEADER([$1],
+  [AC_DEFINE(AS_TR_CPP([HAVE_$1]))], [], [$2])])
+
+# _AC_CHECK_HEADERS_ONE_C(HEADER-FILE, [ACTION-IF-FOUND],
+#    [ACTION-IF-NOT-FOUND], [INCLUDES])
+# -------------------------------------------------------------------------
+# If HEADER-FILE exists, define HAVE_HEADER-FILE and execute ACTION-IF-FOUND.
+# Otherwise execute ACTION-IF-NOT-FOUND.  HEADER-FILE can be a shell variable.
+# Used by AC_CHECK_HEADERS for complex cases.
+# INCLUDES is as for AC_CHECK_HEADER.
+m4_define([_AC_CHECK_HEADERS_ONE_C],
+[AC_CHECK_HEADER([$1],
+  [AC_DEFINE_UNQUOTED(AS_TR_CPP([HAVE_]$1)) $2],
+  [$3], [$4])])
 
 # AC_CHECK_HEADERS(HEADER-FILE...,
 #		   [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND],
@@ -184,17 +215,14 @@ m4_define([AH_CHECK_HEADERS],
 # preprocessor definition HAVE_HEADER_FILE available for each found
 # header.  Either ACTION may include `break' to stop the search.
 AC_DEFUN([AC_CHECK_HEADERS],
-[m4_map_args_w([$1], [_AH_CHECK_HEADER(], [)])]dnl
-[m4_if([$2$3]AS_LITERAL_IF([$1], [[yes]], [[no]]), [yes],
-       [m4_map_args_w([$1], [_$0(], [, [], [], [$4])])],
-       [AS_FOR([AC_header], [ac_header], [$1], [_$0(AC_header, [$2], [$3], [$4])])])dnl
-])# AC_CHECK_HEADERS
+[_$0(m4_validate_w([$1]), [$2], [$3], [$4])])
 
 m4_define([_AC_CHECK_HEADERS],
-[AC_CHECK_HEADER([$1],
-		 [AC_DEFINE_UNQUOTED(AS_TR_CPP([HAVE_]$1)) $2],
-		 [$3], [$4])dnl
-])
+[m4_if([$2$3]AS_LITERAL_IF([$1], [[yes]], [[no]]), [yes],
+       [m4_map_args_w([$1], [_AC_CHECK_HEADERS_ONE_S(], [, [$4])])],
+       [m4_map_args_w([$1], [_AC_CHECK_HEADERS_ONE_U(], [)])]dnl
+       [AS_FOR([AC_header], [ac_header], [$1],
+               [_AC_CHECK_HEADERS_ONE_C(AC_header, [$2], [$3], [$4])])])])
 
 
 # _AC_CHECK_HEADER_ONCE(HEADER-FILE)
@@ -217,10 +245,8 @@ m4_define([_AC_CHECK_HEADER_ONCE],
 # and vice versa.
 AC_DEFUN([AC_CHECK_HEADERS_ONCE],
   [AC_REQUIRE([AC_CHECK_INCLUDES_DEFAULT])]dnl
-  [_AC_CHECK_HEADERS_ONCE([$1])])
+  [m4_map_args_w(m4_validate_w([$1]), [_AC_CHECK_HEADER_ONCE(], [)])])
 
-AC_DEFUN([_AC_CHECK_HEADERS_ONCE],
-  [m4_map_args_w([$1], [_AC_CHECK_HEADER_ONCE(], [)])])
 
 # _AC_HEADERS_EXPANSION(LANG)
 # ---------------------------
@@ -289,8 +315,9 @@ ac_includes_default="\
 # include <unistd.h>
 #endif"
 ])]dnl
-[_AC_CHECK_HEADERS_ONCE(
-  [sys/types.h sys/stat.h strings.h inttypes.h stdint.h unistd.h])]dnl
+[m4_map_args([_AC_CHECK_HEADER_ONCE],
+  [sys/types.h], [sys/stat.h], [strings.h],
+  [inttypes.h], [stdint.h], [unistd.h])]dnl
 dnl For backward compatibility, provide unconditional AC_DEFINEs of
 dnl HAVE_STDLIB_H, HAVE_STRING_H, and STDC_HEADERS.
 [AC_DEFINE([HAVE_STDLIB_H], [1],
diff --git a/lib/autoconf/status.m4 b/lib/autoconf/status.m4
index 5c0a6456..cb337d74 100644
--- a/lib/autoconf/status.m4
+++ b/lib/autoconf/status.m4
@@ -1096,15 +1096,18 @@ m4_define([AC_OUTPUT_COMMANDS_POST])
 #   included, if for instance the user refused a part of the tree.
 #   This is used in _AC_OUTPUT_SUBDIRS.
 AC_DEFUN([AC_CONFIG_SUBDIRS],
+[_$0(m4_validate_w([$1]))])
+
+m4_define([_AC_CONFIG_SUBDIRS],
 [AC_REQUIRE([AC_CONFIG_AUX_DIR_DEFAULT])]dnl
 [AC_REQUIRE([AC_DISABLE_OPTION_CHECKING])]dnl
+[AS_LITERAL_IF([$1], [],
+	       [AC_DIAGNOSE([syntax], [$0: you should use literals])])]dnl
 [m4_map_args_w([$1], [_AC_CONFIG_UNIQUE([SUBDIRS],
   _AC_CONFIG_COMPUTE_DEST(], [))])]dnl
 [m4_append([_AC_LIST_SUBDIRS], [$1], [
 ])]dnl
-[AS_LITERAL_IF([$1], [],
-	       [AC_DIAGNOSE([syntax], [$0: you should use literals])])]dnl
-[AC_SUBST([subdirs], ["$subdirs m4_normalize([$1])"])])
+[AC_SUBST([subdirs], ["$subdirs $1"])])
 
 
 # _AC_OUTPUT_SUBDIRS
diff --git a/lib/m4sugar/m4sugar.m4 b/lib/m4sugar/m4sugar.m4
index 6a191345..b42fc1a6 100644
--- a/lib/m4sugar/m4sugar.m4
+++ b/lib/m4sugar/m4sugar.m4
@@ -2412,6 +2412,27 @@ m4_define([m4_normalize],
 [m4_strip(m4_flatten([$1]))])
 
 
+# m4_validate_w(STRING)
+# ---------------------
+# Expands into m4_normalize(m4_expand([STRING])), but if that is not
+# the same as just m4_normalize([STRING]), issue a warning.
+#
+# This is used in several Autoconf macros that take a
+# whitespace-separated list of symbols as an argument.  Ideally that
+# list would not be expanded before use, but several packages used
+# `dnl' to put comments inside those lists, so they must be expanded
+# for compatibility's sake.
+m4_define([m4_validate_w],
+[_m4_validate_w(m4_normalize([$1]), m4_normalize(m4_expand([$1])))])
+
+m4_define([_m4_validate_w],
+[m4_if([$1], [$2], [],
+  [m4_warn([obsolete], [whitespace-separated list contains macros;
+in a future version of Autoconf they will not be expanded]dnl
+m4_if(m4_bregexp([$1], [\bdn[l]\b]), -1, [], [
+note: `dn@&t@l' is a macro]))])dnl
+[$2]])
+
 
 # m4_join(SEP, ARG1, ARG2...)
 # ---------------------------