Adapt Tcl so it uses a config.h header instead of stuffing all #defs on the

command line. Third parties using generic/tclInt.h, unix/tclAppInit.c or
unix/tcl.m4 should be unaffected. Part of the general TIP#34 project.

1 files changed, 88 insertions, 64 deletions

diff --git a/unix/tcl.m4 b/unix/tcl.m4
index 55175ad..2d8db2d 100644
--- a/unix/tcl.m4
+++ b/unix/tcl.m4
@@ -346,7 +346,7 @@ AC_DEFUN(SC_ENABLE_SHARED, [
     else
 	AC_MSG_RESULT([static])
 	SHARED_BUILD=0
-	AC_DEFINE(STATIC_BUILD)
+	AC_DEFINE(STATIC_BUILD, 1, [Is this a static build?])
     fi
 ])
 
@@ -428,15 +428,17 @@ AC_DEFUN(SC_ENABLE_THREADS, [
 	    AC_MSG_RESULT([yes])
 	fi
 	TCL_THREADS=1
-	AC_DEFINE(TCL_THREADS)
+	AC_DEFINE(TCL_THREADS, 1, [Are we building with threads enabled?])
 	# USE_THREAD_ALLOC tells us to try the special thread-based
 	# allocator that significantly reduces lock contention
-	AC_DEFINE(USE_THREAD_ALLOC)
+	AC_DEFINE(USE_THREAD_ALLOC, 1,
+	    [Do we want to use the threaded memory allocator?])
 	# USE_THREAD_STORAGE tells us to use the new generic thread 
 	# storage subsystem. 
-	AC_DEFINE(USE_THREAD_STORAGE)
-	AC_DEFINE(_REENTRANT)
-	AC_DEFINE(_THREAD_SAFE)
+	AC_DEFINE(USE_THREAD_STORAGE, 1,
+	    [Use the generic thread storage subsystem?])
+	AC_DEFINE(_REENTRANT, 1, [Do we want the reentrant OS API?])
+	AC_DEFINE(_THREAD_SAFE, 1, [Do we want the thread-safe OS API?])
 	AC_CHECK_LIB(pthread,pthread_mutex_init,tcl_ok=yes,tcl_ok=no)
 	if test "$tcl_ok" = "no"; then
 	    # Check a little harder for __pthread_mutex_init in the same
@@ -478,7 +480,8 @@ AC_DEFUN(SC_ENABLE_THREADS, [
 	AC_CHECK_FUNCS(pthread_attr_setstacksize)
 	AC_CHECK_FUNC(pthread_attr_get_np,tcl_ok=yes,tcl_ok=no)
 	if test $tcl_ok = yes ; then
-	    AC_DEFINE(HAVE_PTHREAD_ATTR_GET_NP)
+	    AC_DEFINE(HAVE_PTHREAD_ATTR_GET_NP, 1,
+		[Do we want a BSD-like thread-attribute interface?])
 	    AC_MSG_CHECKING([for pthread_attr_get_np declaration])
 	    AC_CACHE_VAL(tcl_cv_grep_pthread_attr_get_np,
 		AC_EGREP_HEADER(pthread_attr_get_np, pthread.h,
@@ -486,12 +489,14 @@ AC_DEFUN(SC_ENABLE_THREADS, [
 		    tcl_cv_grep_pthread_attr_get_np=missing))
 	    AC_MSG_RESULT($tcl_cv_grep_pthread_attr_get_np)
 	    if test $tcl_cv_grep_pthread_attr_get_np = missing ; then
-		AC_DEFINE(ATTRGETNP_NOT_DECLARED)
+		AC_DEFINE(ATTRGETNP_NOT_DECLARED, 1,
+		    [Is pthread_attr_get_np() declared in <pthread.h>?])
 	    fi
 	else
 	    AC_CHECK_FUNC(pthread_getattr_np,tcl_ok=yes,tcl_ok=no)
 	    if test $tcl_ok = yes ; then
-		AC_DEFINE(HAVE_PTHREAD_GETATTR_NP)
+		AC_DEFINE(HAVE_PTHREAD_GETATTR_NP, 1,
+		    [Do we want a Linux-like thread-attribute interface?])
 		AC_MSG_CHECKING([for pthread_getattr_np declaration])
 		AC_CACHE_VAL(tcl_cv_grep_pthread_getattr_np,
 		    AC_EGREP_HEADER(pthread_getattr_np, pthread.h,
@@ -499,7 +504,8 @@ AC_DEFUN(SC_ENABLE_THREADS, [
 			tcl_cv_grep_pthread_getattr_np=missing))
 		AC_MSG_RESULT($tcl_cv_grep_pthread_getattr_np)
 		if test $tcl_cv_grep_pthread_getattr_np = missing ; then
-		    AC_DEFINE(GETATTRNP_NOT_DECLARED)
+		    AC_DEFINE(GETATTRNP_NOT_DECLARED, 1,
+			[Is pthread_getattr_np declared in <pthread.h>?])
 		fi
 	    fi
 	fi
@@ -551,7 +557,7 @@ AC_DEFUN(SC_ENABLE_SYMBOLS, [
 	LDFLAGS_DEFAULT='$(LDFLAGS_OPTIMIZE)'
 	DBGX=""
 	AC_MSG_RESULT([no])
-	AC_DEFINE(TCL_CFG_OPTIMIZED)
+	AC_DEFINE(TCL_CFG_OPTIMIZED, 1, [Is this an optimized build?])
     else
 	CFLAGS_DEFAULT='$(CFLAGS_DEBUG)'
 	LDFLAGS_DEFAULT='$(LDFLAGS_DEBUG)'
@@ -562,15 +568,15 @@ AC_DEFUN(SC_ENABLE_SYMBOLS, [
     fi
     AC_SUBST(CFLAGS_DEFAULT)
     AC_SUBST(LDFLAGS_DEFAULT)
-    AC_DEFINE(TCL_CFG_DEBUG)
+    AC_DEFINE(TCL_CFG_DEBUG, 1, [Is debugging enabled?])
 
     if test "$tcl_ok" = "mem" -o "$tcl_ok" = "all"; then
-	AC_DEFINE(TCL_MEM_DEBUG)
+	AC_DEFINE(TCL_MEM_DEBUG, 1, [Is memory debugging enabled?])
     fi
 
     if test "$tcl_ok" = "compile" -o "$tcl_ok" = "all"; then
-	AC_DEFINE(TCL_COMPILE_DEBUG)
-	AC_DEFINE(TCL_COMPILE_STATS)
+	AC_DEFINE(TCL_COMPILE_DEBUG, 1, [Is bytecode debugging enabled?])
+	AC_DEFINE(TCL_COMPILE_STATS, 1, [Are bytecode statistics enabled?])
     fi
 
     if test "$tcl_ok" != "yes" -a "$tcl_ok" != "no"; then
@@ -621,7 +627,7 @@ AC_DEFUN(SC_ENABLE_LANGINFO, [
 	    langinfo_ok="no (could not compile with nl_langinfo)";
 	fi
 	if test "$langinfo_ok" = "yes"; then
-	    AC_DEFINE(HAVE_LANGINFO)
+	    AC_DEFINE(HAVE_LANGINFO, 1, [Do we have nl_langinfo()?])
 	fi
     fi
     AC_MSG_RESULT([$langinfo_ok])
@@ -970,7 +976,7 @@ dnl AC_CHECK_TOOL(AR, ar)
 	    AC_CHECK_LIB(bsd, gettimeofday, libbsd=yes, libbsd=no)
 	    if test $libbsd = yes; then
 	    	MATH_LIBS="$MATH_LIBS -lbsd"
-	    	AC_DEFINE(USE_DELTA_FOR_TZ)
+	    	AC_DEFINE(USE_DELTA_FOR_TZ, 1, [Do we need a special AIX hack for timezones?])
 	    fi
 	    ;;
 	BeOS*)
@@ -1021,8 +1027,8 @@ dnl AC_CHECK_TOOL(AR, ar)
 	    ;;
 	HP-UX-*.11.*)
 	    # Use updated header definitions where possible
-	    AC_DEFINE(_XOPEN_SOURCE)          # Use the XOPEN network library
-	    AC_DEFINE(_XOPEN_SOURCE_EXTENDED) # Use the XOPEN network library
+	    AC_DEFINE(_XOPEN_SOURCE, 1, [Do we want to use the XOPEN network library?])
+	    AC_DEFINE(_XOPEN_SOURCE_EXTENDED, 1, [Do we want to use the XOPEN network library?])
 	    LIBS="$LIBS -lxnet"               # Use the XOPEN network library
 
 	    SHLIB_SUFFIX=".sl"
@@ -1199,7 +1205,7 @@ dnl AC_CHECK_TOOL(AR, ar)
 	    fi
 
 	    # XIM peeking works under XFree86.
-	    AC_DEFINE(PEEK_XCLOSEIM)
+	    AC_DEFINE(PEEK_XCLOSEIM, 1, [May we use XIM peeking safely?])
 
 	    ;;
 	GNU*)
@@ -1352,10 +1358,11 @@ dnl AC_CHECK_TOOL(AR, ar)
 	    LD_SEARCH_FLAGS=""
 	    CFLAGS_OPTIMIZE="-Os"
 	    LD_LIBRARY_PATH_VAR="DYLD_LIBRARY_PATH"
-	    AC_DEFINE(MAC_OSX_TCL)
-	    AC_DEFINE(HAVE_CFBUNDLE)
-	    AC_DEFINE(USE_VFORK)
-	    AC_DEFINE(TCL_DEFAULT_ENCODING,"utf-8")
+	    AC_DEFINE(MAC_OSX_TCL, 1, ["Is this a Mac I see before me?"])
+	    AC_DEFINE(HAVE_CFBUNDLE, 1, [Do we have access to Mac bundles?])
+	    AC_DEFINE(USE_VFORK, 1, [Should we use vfork() instead of fork()?])
+	    AC_DEFINE(TCL_DEFAULT_ENCODING,"utf-8",
+		[Are we to override what our default encoding is?])
 	    LIBS="$LIBS -framework CoreFoundation"
 	    ;;
 	NEXTSTEP-*)
@@ -1369,8 +1376,9 @@ dnl AC_CHECK_TOOL(AR, ar)
 	    LD_SEARCH_FLAGS=""
 	    ;;
 	OS/390-*)
-	    CFLAGS_OPTIMIZE=""      # Optimizer is buggy
-	    AC_DEFINE(_OE_SOCKETS)  # needed in sys/socket.h
+	    CFLAGS_OPTIMIZE=""		# Optimizer is buggy
+	    AC_DEFINE(_OE_SOCKETS, 1,	# needed in sys/socket.h
+		[Should OS/390 do the right thing with sockets?])
 	    ;;      
 	OSF1-1.0|OSF1-1.1|OSF1-1.2)
 	    # OSF/1 1.[012] from OSF, and derivatives, including Paragon OSF/1
@@ -1509,8 +1517,9 @@ dnl AC_CHECK_TOOL(AR, ar)
 	    # Note: If _REENTRANT isn't defined, then Solaris
 	    # won't define thread-safe library routines.
 
-	    AC_DEFINE(_REENTRANT)
-	    AC_DEFINE(_POSIX_PTHREAD_SEMANTICS)
+	    AC_DEFINE(_REENTRANT, 1, [Do we want the reentrant OS API?])
+	    AC_DEFINE(_POSIX_PTHREAD_SEMANTICS, 1,
+		[Do we really want to follow the standard? Yes we do!])
 
 	    SHLIB_CFLAGS="-KPIC"
 
@@ -1536,8 +1545,9 @@ dnl AC_CHECK_TOOL(AR, ar)
 	    # Note: If _REENTRANT isn't defined, then Solaris
 	    # won't define thread-safe library routines.
 
-	    AC_DEFINE(_REENTRANT)
-	    AC_DEFINE(_POSIX_PTHREAD_SEMANTICS)
+	    AC_DEFINE(_REENTRANT, 1, [Do we want the reentrant OS API?])
+	    AC_DEFINE(_POSIX_PTHREAD_SEMANTICS, 1,
+		[Do we really want to follow the standard? Yes we do!])
 
 	    SHLIB_CFLAGS="-KPIC"
     
@@ -1614,11 +1624,11 @@ dnl AC_CHECK_TOOL(AR, ar)
     esac
 
     if test "$do64bit" = "yes" -a "$do64bit_ok" = "no" ; then
-    AC_MSG_WARN("64bit support being disabled -- don\'t know magic for this platform")
+	AC_MSG_WARN("64bit support being disabled -- don\'t know magic for this platform")
     fi
 
     if test "$do64bit" = "yes" -a "$do64bit_ok" = "yes" ; then
-	AC_DEFINE(TCL_CFG_DO64BIT)
+	AC_DEFINE(TCL_CFG_DO64BIT, 1, [Is this a 64-bit build?])
     fi
 
     # Step 4: If pseudo-static linking is in use (see K. B. Kenny, "Dynamic
@@ -1656,7 +1666,8 @@ dnl AC_CHECK_TOOL(AR, ar)
     ], tcl_ok=usable, tcl_ok=unusable)
 	AC_MSG_RESULT($tcl_ok)
 	if test $tcl_ok = usable; then
-	    AC_DEFINE(USE_SYS_EXEC_H)
+	    AC_DEFINE(USE_SYS_EXEC_H, 1,
+		[Should we use <sys/exec.h> when doing dynamic loading?])
 	else
 	    AC_MSG_CHECKING(a.out.h)
 	    AC_TRY_COMPILE([#include <a.out.h>],[
@@ -1673,7 +1684,8 @@ dnl AC_CHECK_TOOL(AR, ar)
 	    ], tcl_ok=usable, tcl_ok=unusable)
 	    AC_MSG_RESULT($tcl_ok)
 	    if test $tcl_ok = usable; then
-		AC_DEFINE(USE_A_OUT_H)
+		AC_DEFINE(USE_A_OUT_H, 1,
+		    [Should we use <a.out.h> when doing dynamic loading?])
 	    else
 		AC_MSG_CHECKING(sys/exec_aout.h)
 		AC_TRY_COMPILE([#include <sys/exec_aout.h>],[
@@ -1690,7 +1702,8 @@ dnl AC_CHECK_TOOL(AR, ar)
 		], tcl_ok=usable, tcl_ok=unusable)
 		AC_MSG_RESULT($tcl_ok)
 		if test $tcl_ok = usable; then
-		    AC_DEFINE(USE_SYS_EXEC_AOUT_H)
+		    AC_DEFINE(USE_SYS_EXEC_AOUT_H, 1,
+			[Should we use <sys/exec_aout.h> when doing dynamic loading?])
 		else
 		    DL_OBJS=""
 		fi
@@ -1834,6 +1847,8 @@ dnl        esac
     AC_SUBST(SHLIB_LD_LIBS)
     AC_SUBST(SHLIB_CFLAGS)
     AC_SUBST(SHLIB_SUFFIX)
+    AC_DEFINE_UNQUOTED(TCL_SHLIB_EXT,"${SHLIB_SUFFIX}",
+	[What is the default extension for shared libraries?])
 
     AC_SUBST(MAKE_LIB)
     AC_SUBST(MAKE_STUB_LIB)
@@ -1955,9 +1970,9 @@ int main() {
 }], tcl_cv_api_serial=sgtty, tcl_cv_api_serial=none, tcl_cv_api_serial=none)
     fi])
     case $tcl_cv_api_serial in
-	termios) AC_DEFINE(USE_TERMIOS);;
-	termio)  AC_DEFINE(USE_TERMIO);;
-	sgtty)   AC_DEFINE(USE_SGTTY);;
+	termios) AC_DEFINE(USE_TERMIOS, 1, [Use the termios API for serial lines]);;
+	termio)  AC_DEFINE(USE_TERMIO, 1, [Use the termio API for serial lines]);;
+	sgtty)   AC_DEFINE(USE_SGTTY, 1, [Use the sgtty API for serial lines]);;
     esac
     AC_MSG_RESULT($tcl_cv_api_serial)
 ])
@@ -2016,21 +2031,22 @@ closedir(d);
 ], tcl_ok=yes, tcl_ok=no)
 
     if test $tcl_ok = no; then
-	AC_DEFINE(NO_DIRENT_H)
+	AC_DEFINE(NO_DIRENT_H, 1, [Do we have <dirent.h>?])
     fi
 
     AC_MSG_RESULT($tcl_ok)
-    AC_CHECK_HEADER(errno.h, , [AC_DEFINE(NO_ERRNO_H)])
-    AC_CHECK_HEADER(float.h, , [AC_DEFINE(NO_FLOAT_H)])
-    AC_CHECK_HEADER(values.h, , [AC_DEFINE(NO_VALUES_H)])
+    AC_CHECK_HEADER(errno.h, , [AC_DEFINE(NO_ERRNO_H, 1, [Do we have <errno.h>?])])
+    AC_CHECK_HEADER(float.h, , [AC_DEFINE(NO_FLOAT_H, 1, [Do we have <float.h>?])])
+    AC_CHECK_HEADER(values.h, , [AC_DEFINE(NO_VALUES_H, 1, [Do we have <values.h>?])])
     AC_CHECK_HEADER(limits.h,
-	[AC_DEFINE(HAVE_LIMITS_H)], [AC_DEFINE(NO_LIMITS_H)])
+	[AC_DEFINE(HAVE_LIMITS_H, 1, [Do we have <limits.h>?])],
+	[AC_DEFINE(NO_LIMITS_H, 1, [Do we have <limits.h>?])])
     AC_CHECK_HEADER(stdlib.h, tcl_ok=1, tcl_ok=0)
     AC_EGREP_HEADER(strtol, stdlib.h, , tcl_ok=0)
     AC_EGREP_HEADER(strtoul, stdlib.h, , tcl_ok=0)
     AC_EGREP_HEADER(strtod, stdlib.h, , tcl_ok=0)
     if test $tcl_ok = 0; then
-	AC_DEFINE(NO_STDLIB_H)
+	AC_DEFINE(NO_STDLIB_H, 1, [Do we have <stdlib.h>?])
     fi
     AC_CHECK_HEADER(string.h, tcl_ok=1, tcl_ok=0)
     AC_EGREP_HEADER(strstr, string.h, , tcl_ok=0)
@@ -2040,11 +2056,11 @@ closedir(d);
     # set and why.
 
     if test $tcl_ok = 0; then
-	AC_DEFINE(NO_STRING_H)
+	AC_DEFINE(NO_STRING_H, 1, [Do we have <string.h>?])
     fi
 
-    AC_CHECK_HEADER(sys/wait.h, , [AC_DEFINE(NO_SYS_WAIT_H)])
-    AC_CHECK_HEADER(dlfcn.h, , [AC_DEFINE(NO_DLFCN_H)])
+    AC_CHECK_HEADER(sys/wait.h, , [AC_DEFINE(NO_SYS_WAIT_H, 1, [Do we have <sys/wait.h>?])])
+    AC_CHECK_HEADER(dlfcn.h, , [AC_DEFINE(NO_DLFCN_H, 1, [Do we have <dlfcn.h>?])])
 
     # OS/390 lacks sys/param.h (and doesn't need it, by chance).
     AC_HAVE_HEADERS(sys/param.h)
@@ -2185,15 +2201,15 @@ AC_DEFUN(SC_BLOCKING_STYLE, [
 	# code (JO, 5/31/97).
 
 	OSF*)
-	    AC_DEFINE(USE_FIONBIO)
+	    AC_DEFINE(USE_FIONBIO, 1, [Should we use FIONBIO?])
 	    AC_MSG_RESULT(FIONBIO)
 	    ;;
 	SunOS-4*)
-	    AC_DEFINE(USE_FIONBIO)
+	    AC_DEFINE(USE_FIONBIO, 1, [Should we use FIONBIO?])
 	    AC_MSG_RESULT(FIONBIO)
 	    ;;
 	ULTRIX-4.*)
-	    AC_DEFINE(USE_FIONBIO)
+	    AC_DEFINE(USE_FIONBIO, 1, [Should we use FIONBIO?])
 	    AC_MSG_RESULT(FIONBIO)
 	    ;;
 	*)
@@ -2234,7 +2250,7 @@ AC_DEFUN(SC_TIME_HANDLER, [
 	    tcl_cv_member_tm_tzadj=yes, tcl_cv_member_tm_tzadj=no))
     AC_MSG_RESULT($tcl_cv_member_tm_tzadj)
     if test $tcl_cv_member_tm_tzadj = yes ; then
-	AC_DEFINE(HAVE_TM_TZADJ)
+	AC_DEFINE(HAVE_TM_TZADJ, 1, [Should we use the tm_tzadj field of struct tm?])
     fi
 
     AC_MSG_CHECKING([tm_gmtoff in struct tm])
@@ -2243,7 +2259,7 @@ AC_DEFUN(SC_TIME_HANDLER, [
 	    tcl_cv_member_tm_gmtoff=yes, tcl_cv_member_tm_gmtoff=no))
     AC_MSG_RESULT($tcl_cv_member_tm_gmtoff)
     if test $tcl_cv_member_tm_gmtoff = yes ; then
-	AC_DEFINE(HAVE_TM_GMTOFF)
+	AC_DEFINE(HAVE_TM_GMTOFF, 1, [Should we use the tm_gmtoff field of struct tm?])
     fi
 
     #
@@ -2259,7 +2275,7 @@ AC_DEFUN(SC_TIME_HANDLER, [
 	    tcl_cv_timezone_long=yes, tcl_cv_timezone_long=no))
     AC_MSG_RESULT($tcl_cv_timezone_long)
     if test $tcl_cv_timezone_long = yes ; then
-	AC_DEFINE(HAVE_TIMEZONE_VAR)
+	AC_DEFINE(HAVE_TIMEZONE_VAR, 1, [Should we use the global timezone variable?])
     else
 	#
 	# On some systems (eg IRIX 6.2), timezone is a time_t and not a long.
@@ -2273,7 +2289,7 @@ AC_DEFUN(SC_TIME_HANDLER, [
 		tcl_cv_timezone_time=yes, tcl_cv_timezone_time=no))
 	AC_MSG_RESULT($tcl_cv_timezone_time)
 	if test $tcl_cv_timezone_time = yes ; then
-	    AC_DEFINE(HAVE_TIMEZONE_VAR)
+	    AC_DEFINE(HAVE_TIMEZONE_VAR, 1, [Should we use the global timezone variable?])
 	fi
     fi
 ])
@@ -2329,7 +2345,7 @@ AC_DEFUN(SC_BUGGY_STRTOD, [
 	    AC_MSG_RESULT(buggy)
 	    AC_LIBOBJ([fixstrtod])
 	    USE_COMPAT=1
-	    AC_DEFINE(strtod, fixstrtod)
+	    AC_DEFINE(strtod, fixstrtod, [Do we want to use the strtod() in compat?])
 	fi
     fi
 ])
@@ -2372,7 +2388,8 @@ AC_DEFUN(SC_TCL_LINK_LIBS, [
     #--------------------------------------------------------------------
 
     AC_CHECK_LIB(inet, main, [LIBS="$LIBS -linet"])
-    AC_CHECK_HEADER(net/errno.h, [AC_DEFINE(HAVE_NET_ERRNO_H)])
+    AC_CHECK_HEADER(net/errno.h, [
+	AC_DEFINE(HAVE_NET_ERRNO_H, 1, [Do we have <net/errno.h>?])])
 
     #--------------------------------------------------------------------
     #	Check for the existence of the -lsocket and -lnsl libraries.
@@ -2432,7 +2449,7 @@ AC_DEFUN(SC_TCL_EARLY_FLAG,[
 		[tcl_cv_flag_]translit($1,[A-Z],[a-z])=yes,
 		[tcl_cv_flag_]translit($1,[A-Z],[a-z])=no)))
     if test ["x${tcl_cv_flag_]translit($1,[A-Z],[a-z])[}" = "xyes"] ; then
-	AC_DEFINE($1)
+	AC_DEFINE($1, 1, [Add the ]$1[ flag when building])
 	tcl_flags="$tcl_flags $1"
     fi])
 
@@ -2482,10 +2499,11 @@ AC_DEFUN(SC_TCL_64BIT_FLAGS, [
             case 1: case (sizeof(]${tcl_type_64bit}[)==sizeof(long)): ; 
         }],tcl_cv_type_64bit=${tcl_type_64bit})])
     if test "${tcl_cv_type_64bit}" = none ; then
-	AC_DEFINE(TCL_WIDE_INT_IS_LONG)
+	AC_DEFINE(TCL_WIDE_INT_IS_LONG, 1, [Are wide integers to be implemented with C 'long's?])
 	AC_MSG_RESULT(using long)
     else
-	AC_DEFINE_UNQUOTED(TCL_WIDE_INT_TYPE,${tcl_cv_type_64bit})
+	AC_DEFINE_UNQUOTED(TCL_WIDE_INT_TYPE,${tcl_cv_type_64bit},
+	    [What type should be used to define wide integers?])
 	AC_MSG_RESULT(${tcl_cv_type_64bit})
 
 	# Now check for auxiliary declarations
@@ -2495,7 +2513,7 @@ AC_DEFUN(SC_TCL_64BIT_FLAGS, [
 #include <sys/dirent.h>],[struct dirent64 p;],
 		tcl_cv_struct_dirent64=yes,tcl_cv_struct_dirent64=no)])
 	if test "x${tcl_cv_struct_dirent64}" = "xyes" ; then
-	    AC_DEFINE(HAVE_STRUCT_DIRENT64)
+	    AC_DEFINE(HAVE_STRUCT_DIRENT64, 1, [Is 'struct dirent64' in <sys/types.h>?])
 	fi
 	AC_MSG_RESULT(${tcl_cv_struct_dirent64})
 
@@ -2505,7 +2523,7 @@ AC_DEFUN(SC_TCL_64BIT_FLAGS, [
 ],
 		tcl_cv_struct_stat64=yes,tcl_cv_struct_stat64=no)])
 	if test "x${tcl_cv_struct_stat64}" = "xyes" ; then
-	    AC_DEFINE(HAVE_STRUCT_STAT64)
+	    AC_DEFINE(HAVE_STRUCT_STAT64, 1, [Is 'struct stat64' in <sys/stat.h>?])
 	fi
 	AC_MSG_RESULT(${tcl_cv_struct_stat64})
 
@@ -2515,7 +2533,7 @@ AC_DEFUN(SC_TCL_64BIT_FLAGS, [
 ],
 		tcl_cv_type_off64_t=yes,tcl_cv_type_off64_t=no)])
 	if test "x${tcl_cv_type_off64_t}" = "xyes" ; then
-	    AC_DEFINE(HAVE_TYPE_OFF64_T)
+	    AC_DEFINE(HAVE_TYPE_OFF64_T, 1, [Is off64_t in <sys/types.h>?])
 	fi
 	AC_MSG_RESULT(${tcl_cv_type_off64_t})
     fi])
@@ -2541,7 +2559,13 @@ AC_DEFUN(SC_TCL_CFG_ENCODING, [
     AC_ARG_WITH(encoding, [  --with-encoding              encoding for configuration values], with_tcencoding=${withval})
 
     if test x"${with_tcencoding}" != x ; then
-	AC_DEFINE_UNQUOTED(TCL_CFGVAL_ENCODING,"${with_tcencoding}")
+	AC_DEFINE_UNQUOTED(TCL_CFGVAL_ENCODING,"${with_tcencoding}",
+	    [What encoding should be used for embedded configuration info?])
     else
-	AC_DEFINE(TCL_CFGVAL_ENCODING,"iso8859-1")
+	AC_DEFINE(TCL_CFGVAL_ENCODING,"iso8859-1",
+	    [What encoding should be used for embedded configuration info?])
     fi])
+
+# Local Variables:
+# mode: autoconf
+# End: