fixed local Q-Register management on certain broken platforms

 * on MSVCRT/MinGW, space allocated with alloca()/g_newa() was apparently
   freed once the first exception was caught.
   This prevented the proper destruction of local Q-Reg tables and
   broke the Windows port.
 * Since all alternatives to alloca() like VLAs are not practical,
   the default Q-Register initialization has been moved out of the
   QRegisterTable constructor into QRegisterTable::insert_defaults().
 * The remaining QRegisterTable initialization and destruction is
   very cheap, so we simply reserve an empty QRegisterTable for
   local registers on every Execute::macro() call.
   The default registers are only initialized when required, though.
 * All of this has to change anyway once we replace the
   C++ call-stack approach to macro calls with our own macro
   call frame memory management.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/main.cpp b/src/main.cpp
index bc82093..ce00c0a 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -384,6 +384,8 @@ main(int argc, char **argv)
 	 */
 	QRegisters::view.initialize();
 
+	/* the default registers (A-Z and 0-9) */
+	QRegisters::globals.insert_defaults();
 	/* search string and status register */
 	QRegisters::globals.insert("_");
 	/* replacement string register */
@@ -395,6 +397,8 @@ main(int argc, char **argv)
 	/* environment defaults and registers */
 	initialize_environment(argv[0]);
 
+	/* the default registers (A-Z and 0-9) */
+	local_qregs.insert_defaults();
 	QRegisters::locals = &local_qregs;
 
 	ring.edit((const gchar *)NULL);