Workaround for https://core.tcl-lang.org/thread/tktview/30e201c711

Index: configure
==================================================================
--- pkgs/thread3.0.6/configure.orig	
+++ pkgs/thread3.0.6/configure	
@@ -1391,11 +1391,11 @@
                           shared builds (default: on)
   --enable-64bit          enable 64bit support (default: off)
   --enable-64bit-vis      enable 64bit Sparc VIS support (default: off)
   --disable-rpath         disable rpath support (default: on)
   --enable-symbols        build with debugging symbols (default: off)
-  --enable-zipfs          build with Zipfs support (default: on)
+  --enable-zipfs          build with Zipfs support (default: off)
 
 Optional Packages:
   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
   --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no)
   --with-tcl              directory containing tcl configuration
@@ -9688,11 +9688,11 @@
     # Check whether --enable-zipfs was given.
 if test ${enable_zipfs+y}
 then :
   enableval=$enable_zipfs; tcl_ok=$enableval
 else case e in #(
-  e) tcl_ok=yes ;;
+  e) tcl_ok=no ;;
 esac
 fi
 
     if test "$tcl_ok" = "yes" -a "x$enable_framework" != "xyes"; then
 	ZIPFS_BUILD=1


Index: configure
==================================================================
--- pkgs/thread3.0.6/configure.orig
+++ pkgs/thread3.0.6/configure
@@ -9699,10 +9699,13 @@
 	THREAD_ZIP_FILE=lib${PACKAGE_NAME}${PACKAGE_VERSION}.zip
     else
 	ZIPFS_BUILD=0
 	THREAD_ZIP_FILE=
     fi
+else
+    ZIPFS_BUILD=0
+    THREAD_ZIP_FILE=
 fi
 
 # Do checking message here to not mess up interleaved configure output
 { printf '%s\n' "$as_me:${as_lineno-$LINENO}: checking for building with zipfs" >&5
 printf %s "checking for building with zipfs... " >&6; }