* win/configure: Regen.

	* win/configure.in:
	* win/tclWin32Dll.c (TclpCheckStackSpace): Rework
	the SEH exception handler logic to avoid using
	the stack since alloca will modify the stack.
	This was causing a nasty bug that would set the
	exception handler to 0 because it tried to pop
	the previous exception handler off the top of
	the stack.

4 files changed, 126 insertions, 33 deletions

diff --git a/ChangeLog b/ChangeLog
index 194170b..e45a864 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2003-01-24  Mo DeJong  <mdejong@users.sourceforge.net>
+
+	* win/configure: Regen.
+	* win/configure.in:
+	* win/tclWin32Dll.c (TclpCheckStackSpace): Rework
+	the SEH exception handler logic to avoid using
+	the stack since alloca will modify the stack.
+	This was causing a nasty bug that would set the
+	exception handler to 0 because it tried to pop
+	the previous exception handler off the top of
+	the stack.
+
 2003-01-23  Donal K. Fellows  <fellowsd@cs.man.ac.uk>
 
 	* doc/lset.n: Fixed fault in return values from lset in
diff --git a/win/configure b/win/configure
index 248408e..aae48ca 100755
--- a/win/configure
+++ b/win/configure
@@ -1167,18 +1167,63 @@ EOF
 
 fi
 
+# Check to see if malloc.h is missing the alloca function
+# declaration. This is known to be a problem with Mingw.
+
+echo $ac_n "checking for alloca declaration in malloc.h""... $ac_c" 1>&6
+echo "configure:1175: checking for alloca declaration in malloc.h" >&5
+if eval "test \"`echo '$''{'tcl_cv_malloc_decl_alloca'+set}'`\" = set"; then
+  echo $ac_n "(cached) $ac_c" 1>&6
+else
+  cat > conftest.$ac_ext <<EOF
+#line 1180 "configure"
+#include "confdefs.h"
+
+#include <malloc.h>
+
+int main() {
+
+  size_t arg = 0;
+  void* ptr;
+  ptr = alloca;
+  ptr = alloca(arg);
+
+; return 0; }
+EOF
+if { (eval echo configure:1194: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+  rm -rf conftest*
+  tcl_cv_malloc_decl_alloca=yes
+else
+  echo "configure: failed program was:" >&5
+  cat conftest.$ac_ext >&5
+  rm -rf conftest*
+  tcl_cv_malloc_decl_alloca=no
+fi
+rm -f conftest*
+
+fi
+
+echo "$ac_t""$tcl_cv_malloc_decl_alloca" 1>&6
+if test "$tcl_cv_malloc_decl_alloca" = "no" ; then
+    cat >> confdefs.h <<\EOF
+#define HAVE_NO_ALLOC_DECL 1
+EOF
+
+fi
+
+
 #--------------------------------------------------------------------
 # Determines the correct binary file extension (.o, .obj, .exe etc.)
 #--------------------------------------------------------------------
 
 echo $ac_n "checking for object suffix""... $ac_c" 1>&6
-echo "configure:1176: checking for object suffix" >&5
+echo "configure:1221: checking for object suffix" >&5
 if eval "test \"`echo '$''{'ac_cv_objext'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   rm -f conftest*
 echo 'int i = 1;' > conftest.$ac_ext
-if { (eval echo configure:1182: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1227: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   for ac_file in conftest.*; do
     case $ac_file in
     *.c) ;;
@@ -1196,19 +1241,19 @@ OBJEXT=$ac_cv_objext
 ac_objext=$ac_cv_objext
 
 echo $ac_n "checking for mingw32 environment""... $ac_c" 1>&6
-echo "configure:1200: checking for mingw32 environment" >&5
+echo "configure:1245: checking for mingw32 environment" >&5
 if eval "test \"`echo '$''{'ac_cv_mingw32'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1205 "configure"
+#line 1250 "configure"
 #include "confdefs.h"
 
 int main() {
 return __MINGW32__;
 ; return 0; }
 EOF
-if { (eval echo configure:1212: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1257: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_mingw32=yes
 else
@@ -1227,7 +1272,7 @@ test "$ac_cv_mingw32" = yes && MINGW32=yes
 
 
 echo $ac_n "checking for executable suffix""... $ac_c" 1>&6
-echo "configure:1231: checking for executable suffix" >&5
+echo "configure:1276: checking for executable suffix" >&5
 if eval "test \"`echo '$''{'ac_cv_exeext'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1237,7 +1282,7 @@ else
   rm -f conftest*
   echo 'int main () { return 0; }' > conftest.$ac_ext
   ac_cv_exeext=
-  if { (eval echo configure:1241: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; }; then
+  if { (eval echo configure:1286: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; }; then
     for file in conftest.*; do
       case $file in
       *.c | *.o | *.obj) ;;
@@ -1264,7 +1309,7 @@ ac_exeext=$EXEEXT
 
 
     echo $ac_n "checking for building with threads""... $ac_c" 1>&6
-echo "configure:1268: checking for building with threads" >&5
+echo "configure:1313: checking for building with threads" >&5
     # Check whether --enable-threads or --disable-threads was given.
 if test "${enable_threads+set}" = set; then
   enableval="$enable_threads"
@@ -1301,7 +1346,7 @@ EOF
 
 
     echo $ac_n "checking how to build libraries""... $ac_c" 1>&6
-echo "configure:1305: checking how to build libraries" >&5
+echo "configure:1350: checking how to build libraries" >&5
     # Check whether --enable-shared or --disable-shared was given.
 if test "${enable_shared+set}" = set; then
   enableval="$enable_shared"
@@ -1342,7 +1387,7 @@ EOF
     # Step 0: Enable 64 bit support?
 
     echo $ac_n "checking if 64bit support is requested""... $ac_c" 1>&6
-echo "configure:1346: checking if 64bit support is requested" >&5
+echo "configure:1391: checking if 64bit support is requested" >&5
     # Check whether --enable-64bit or --disable-64bit was given.
 if test "${enable_64bit+set}" = set; then
   enableval="$enable_64bit"
@@ -1359,7 +1404,7 @@ fi
     # Extract the first word of "cygpath", so it can be a program name with args.
 set dummy cygpath; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1363: checking for $ac_word" >&5
+echo "configure:1408: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CYGPATH'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1403,9 +1448,9 @@ fi
 	echo "END" >> $conftest
 
 	echo $ac_n "checking for Windows native path bug in windres""... $ac_c" 1>&6
-echo "configure:1407: checking for Windows native path bug in windres" >&5
+echo "configure:1452: checking for Windows native path bug in windres" >&5
 	cyg_conftest=`$CYGPATH $conftest`
-	if { ac_try='$RC -o conftest.res.o $cyg_conftest'; { (eval echo configure:1409: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } ; then
+	if { ac_try='$RC -o conftest.res.o $cyg_conftest'; { (eval echo configure:1454: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } ; then
 	    echo "$ac_t""no" 1>&6
 	else
 	    echo "$ac_t""yes" 1>&6
@@ -1424,7 +1469,7 @@ echo "configure:1407: checking for Windows native path bug in windres" >&5
     # set various compiler flags depending on whether we are using gcc or cl
 
     echo $ac_n "checking compiler flags""... $ac_c" 1>&6
-echo "configure:1428: checking compiler flags" >&5
+echo "configure:1473: checking compiler flags" >&5
     if test "${GCC}" = "yes" ; then
 	if test "$do64bit" = "yes" ; then
 	    echo "configure: warning: "64bit mode not supported with GCC on Windows"" 1>&2
@@ -1640,7 +1685,7 @@ echo "configure:1428: checking compiler flags" >&5
 
 
     echo $ac_n "checking for build with symbols""... $ac_c" 1>&6
-echo "configure:1644: checking for build with symbols" >&5
+echo "configure:1689: checking for build with symbols" >&5
     # Check whether --enable-symbols or --disable-symbols was given.
 if test "${enable_symbols+set}" = set; then
   enableval="$enable_symbols"
@@ -1700,7 +1745,7 @@ TCL_DBGX=${DBGX}
 #--------------------------------------------------------------------
 
 echo $ac_n "checking how to run the C preprocessor""... $ac_c" 1>&6
-echo "configure:1704: checking how to run the C preprocessor" >&5
+echo "configure:1749: checking how to run the C preprocessor" >&5
 # On Suns, sometimes $CPP names a directory.
 if test -n "$CPP" && test -d "$CPP"; then
   CPP=
@@ -1715,13 +1760,13 @@ else
   # On the NeXT, cc -E runs the code through the compiler's parser,
   # not just through cpp.
   cat > conftest.$ac_ext <<EOF
-#line 1719 "configure"
+#line 1764 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1725: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1770: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1732,13 +1777,13 @@ else
   rm -rf conftest*
   CPP="${CC-cc} -E -traditional-cpp"
   cat > conftest.$ac_ext <<EOF
-#line 1736 "configure"
+#line 1781 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1742: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1787: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1749,13 +1794,13 @@ else
   rm -rf conftest*
   CPP="${CC-cc} -nologo -E"
   cat > conftest.$ac_ext <<EOF
-#line 1753 "configure"
+#line 1798 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1759: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1804: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1781,17 +1826,17 @@ echo "$ac_t""$CPP" 1>&6
 
 ac_safe=`echo "errno.h" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for errno.h""... $ac_c" 1>&6
-echo "configure:1785: checking for errno.h" >&5
+echo "configure:1830: checking for errno.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1790 "configure"
+#line 1835 "configure"
 #include "confdefs.h"
 #include <errno.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1795: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1840: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
diff --git a/win/configure.in b/win/configure.in
index b641255..0b99959 100644
--- a/win/configure.in
+++ b/win/configure.in
@@ -3,7 +3,7 @@
 # generate the file "configure", which is run during Tcl installation
 # to configure the system for the local environment.
 #
-# RCS: @(#) $Id: configure.in,v 1.62 2003/01/13 07:01:06 mdejong Exp $
+# RCS: @(#) $Id: configure.in,v 1.63 2003/01/24 08:04:28 mdejong Exp $
 
 AC_INIT(../generic/tcl.h)
 AC_PREREQ(2.13)
@@ -194,6 +194,29 @@ if test "$tcl_cv_winnt_ignore_void" = "yes" ; then
             [Defined when cygwin/mingw ignores VOID define in winnt.h])
 fi
 
+# Check to see if malloc.h is missing the alloca function
+# declaration. This is known to be a problem with Mingw.
+
+AC_CACHE_CHECK(for alloca declaration in malloc.h,
+    tcl_cv_malloc_decl_alloca,
+AC_TRY_COMPILE([
+#include <malloc.h>
+],
+[
+  size_t arg = 0;
+  void* ptr;
+  ptr = alloca;
+  ptr = alloca(arg);
+],
+        tcl_cv_malloc_decl_alloca=yes,
+        tcl_cv_malloc_decl_alloca=no)
+)
+if test "$tcl_cv_malloc_decl_alloca" = "no" ; then
+    AC_DEFINE(HAVE_NO_ALLOC_DECL, 1,
+            [Defined when alloca decl is missing from malloc.h])
+fi
+
+
 #--------------------------------------------------------------------
 # Determines the correct binary file extension (.o, .obj, .exe etc.)
 #--------------------------------------------------------------------
diff --git a/win/tclWin32Dll.c b/win/tclWin32Dll.c
index ac9e8cd..1c029f8 100644
--- a/win/tclWin32Dll.c
+++ b/win/tclWin32Dll.c
@@ -9,11 +9,16 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclWin32Dll.c,v 1.20 2003/01/16 19:01:59 mdejong Exp $
+ * RCS: @(#) $Id: tclWin32Dll.c,v 1.21 2003/01/24 08:04:29 mdejong Exp $
  */
 
 #include "tclWinInt.h"
 
+#if defined(HAVE_NO_ALLOC_DECL)
+void*  __cdecl _alloca(size_t size);
+#define alloca _alloca
+#endif /* HAVE_NO_ALLOC_DECL */
+
 /*
  * The following data structures are used when loading the thunking 
  * library for execing child processes under Win32s.
@@ -40,6 +45,9 @@ static int platformId;		/* Running under NT, or 95/98? */
 #ifdef HAVE_NO_SEH
 static void *ESP;
 static void *EBP;
+static void* HANDLER[2];
+static void* NEW_HANDLER = &(HANDLER[0]);
+static void* OLD_HANDLER = &(HANDLER[1]);
 #endif /* HAVE_NO_SEH */
 
 /*
@@ -378,9 +386,12 @@ TclpCheckStackSpace()
             "movl  %ebp, _EBP");
 
     __asm__ __volatile__ (
-            "pushl $__except_checkstackspace_handler" "\n\t"
-            "pushl %fs:0" "\n\t"
-            "mov   %esp, %fs:0");
+            "movl  %fs:0, %eax" "\n\t"
+            "movl  %eax, _OLD_HANDLER" "\n\t"
+            "movl  __except_checkstackspace_handler, %eax" "\n\t"
+            "movl  %eax, _NEW_HANDLER" "\n\t"
+            "movl  _HANDLER, %eax" "\n\t"
+            "movl  %eax, %fs:0");
 #else
     __try {
 #endif /* HAVE_NO_SEH */
@@ -395,9 +406,8 @@ TclpCheckStackSpace()
 
     __asm__ __volatile__ (
             "checkstackspace_pop:" "\n\t"
-            "mov   (%esp), %eax" "\n\t"
-            "mov   %eax, %fs:0" "\n\t"
-            "add   $8, %esp");
+            "mov   _OLD_HANDLER, %eax"  "\n\t"
+            "mov   %eax, %fs:0");
 #else
     } __except (EXCEPTION_EXECUTE_HANDLER) {}
 #endif /* HAVE_NO_SEH */
@@ -625,6 +635,9 @@ static void squelch_warnings()
     ptr = _except_checkstackspace_handler;
     ESP = 0;
     EBP = 0;
+    OLD_HANDLER = 0;
+    NEW_HANDLER = 0;
+    HANDLER[0] = 0;
     squelch_warnings();
 }
 #endif /* HAVE_NO_SEH */