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authorAndrew Cagney <cagney@redhat.com>2004-04-06 15:30:19 +0000
committerAndrew Cagney <cagney@redhat.com>2004-04-06 15:30:19 +0000
commit35dab8a28b8c74c605f6d5b796792047f6001aae (patch)
treedda87e42c8c5c7207c59e532a54e41713a4a31d2 /gdb/hppa-tdep.c
parent8dd5ca69fbadfbb160d48c4d704ab8e0d2bddb4b (diff)
downloadgdb-35dab8a28b8c74c605f6d5b796792047f6001aae.tar.gz
2004-04-06 Randolph Chung <tausq@debian.org>
Committed by Andrew Cagney (mechanical change). * hppa-tdep.c: (args_for_find_stub, hp_som_som_object_present, exception_catchpoints_are_fragile, find_stub_with_shl_get, cover_find_stub_with_shl_get, initialize_hp_cxx_exception_support, child_enable_exception_callback, current_ex_event, null_symtab_and_line, child_get_current_exception_event, HP_ACC_EH_notify_hook, HP_ACC_EH_set_hook_value, HP_ACC_EH_notify_callback, HP_ACC_EH_break, HP_ACC_EH_catch_throw, HP_ACC_EH_catch_catch, __eh_notification, hp_cxx_exception_support, hp_cxx_exception_support_initialized, eh_notify_hook_addr, eh_notify_callback_addr, eh_break_addr, eh_catch_catch_addr, eh_catch_throw_addr, break_callback_sal, setup_d_pid_in_inferior): Move hpux-specific definitions ... * hppa-hpux-tdep.c: ... to here.
Diffstat (limited to 'gdb/hppa-tdep.c')
-rw-r--r--gdb/hppa-tdep.c568
1 files changed, 0 insertions, 568 deletions
diff --git a/gdb/hppa-tdep.c b/gdb/hppa-tdep.c
index ca6331d7c48..798395b92dd 100644
--- a/gdb/hppa-tdep.c
+++ b/gdb/hppa-tdep.c
@@ -48,12 +48,10 @@
#include <sys/types.h>
#endif
-#include <dl.h>
#include <sys/param.h>
#include <signal.h>
#include <sys/ptrace.h>
-#include <machine/save_state.h>
#ifdef COFF_ENCAPSULATE
#include "a.out.encap.h"
@@ -152,24 +150,8 @@ CORE_ADDR hppa_smash_text_address (CORE_ADDR addr);
CORE_ADDR hppa_target_read_pc (ptid_t ptid);
void hppa_target_write_pc (CORE_ADDR v, ptid_t ptid);
-typedef struct
- {
- struct minimal_symbol *msym;
- CORE_ADDR solib_handle;
- CORE_ADDR return_val;
- }
-args_for_find_stub;
-
-static int cover_find_stub_with_shl_get (void *);
-
static int is_pa_2 = 0; /* False */
-/* This is declared in symtab.c; set to 1 in hp-symtab-read.c */
-extern int hp_som_som_object_present;
-
-/* In breakpoint.c */
-extern int exception_catchpoints_are_fragile;
-
/* Handle 32/64-bit struct return conventions. */
static enum return_value_convention
@@ -1058,102 +1040,6 @@ hppa64_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr)
}
-/* elz: Used to lookup a symbol in the shared libraries.
- This function calls shl_findsym, indirectly through a
- call to __d_shl_get. __d_shl_get is in end.c, which is always
- linked in by the hp compilers/linkers.
- The call to shl_findsym cannot be made directly because it needs
- to be active in target address space.
- inputs: - minimal symbol pointer for the function we want to look up
- - address in target space of the descriptor for the library
- where we want to look the symbol up.
- This address is retrieved using the
- som_solib_get_solib_by_pc function (somsolib.c).
- output: - real address in the library of the function.
- note: the handle can be null, in which case shl_findsym will look for
- the symbol in all the loaded shared libraries.
- files to look at if you need reference on this stuff:
- dld.c, dld_shl_findsym.c
- end.c
- man entry for shl_findsym */
-
-CORE_ADDR
-find_stub_with_shl_get (struct minimal_symbol *function, CORE_ADDR handle)
-{
- struct symbol *get_sym, *symbol2;
- struct minimal_symbol *buff_minsym, *msymbol;
- struct type *ftype;
- struct value **args;
- struct value *funcval;
- struct value *val;
-
- int x, namelen, err_value, tmp = -1;
- CORE_ADDR endo_buff_addr, value_return_addr, errno_return_addr;
- CORE_ADDR stub_addr;
-
-
- args = alloca (sizeof (struct value *) * 8); /* 6 for the arguments and one null one??? */
- funcval = find_function_in_inferior ("__d_shl_get");
- get_sym = lookup_symbol ("__d_shl_get", NULL, VAR_DOMAIN, NULL, NULL);
- buff_minsym = lookup_minimal_symbol ("__buffer", NULL, NULL);
- msymbol = lookup_minimal_symbol ("__shldp", NULL, NULL);
- symbol2 = lookup_symbol ("__shldp", NULL, VAR_DOMAIN, NULL, NULL);
- endo_buff_addr = SYMBOL_VALUE_ADDRESS (buff_minsym);
- namelen = strlen (DEPRECATED_SYMBOL_NAME (function));
- value_return_addr = endo_buff_addr + namelen;
- ftype = check_typedef (SYMBOL_TYPE (get_sym));
-
- /* do alignment */
- if ((x = value_return_addr % 64) != 0)
- value_return_addr = value_return_addr + 64 - x;
-
- errno_return_addr = value_return_addr + 64;
-
-
- /* set up stuff needed by __d_shl_get in buffer in end.o */
-
- target_write_memory (endo_buff_addr, DEPRECATED_SYMBOL_NAME (function), namelen);
-
- target_write_memory (value_return_addr, (char *) &tmp, 4);
-
- target_write_memory (errno_return_addr, (char *) &tmp, 4);
-
- target_write_memory (SYMBOL_VALUE_ADDRESS (msymbol),
- (char *) &handle, 4);
-
- /* now prepare the arguments for the call */
-
- args[0] = value_from_longest (TYPE_FIELD_TYPE (ftype, 0), 12);
- args[1] = value_from_pointer (TYPE_FIELD_TYPE (ftype, 1), SYMBOL_VALUE_ADDRESS (msymbol));
- args[2] = value_from_pointer (TYPE_FIELD_TYPE (ftype, 2), endo_buff_addr);
- args[3] = value_from_longest (TYPE_FIELD_TYPE (ftype, 3), TYPE_PROCEDURE);
- args[4] = value_from_pointer (TYPE_FIELD_TYPE (ftype, 4), value_return_addr);
- args[5] = value_from_pointer (TYPE_FIELD_TYPE (ftype, 5), errno_return_addr);
-
- /* now call the function */
-
- val = call_function_by_hand (funcval, 6, args);
-
- /* now get the results */
-
- target_read_memory (errno_return_addr, (char *) &err_value, sizeof (err_value));
-
- target_read_memory (value_return_addr, (char *) &stub_addr, sizeof (stub_addr));
- if (stub_addr <= 0)
- error ("call to __d_shl_get failed, error code is %d", err_value);
-
- return (stub_addr);
-}
-
-/* Cover routine for find_stub_with_shl_get to pass to catch_errors */
-static int
-cover_find_stub_with_shl_get (void *args_untyped)
-{
- args_for_find_stub *args = args_untyped;
- args->return_val = find_stub_with_shl_get (args->msym, args->solib_handle);
- return 0;
-}
-
/* Get the PC from %r31 if currently in a syscall. Also mask out privilege
bits. */
@@ -2494,460 +2380,6 @@ hppa_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
return frame_unwind_register_signed (next_frame, PCOQ_HEAD_REGNUM) & ~3;
}
-/* Exception handling support for the HP-UX ANSI C++ compiler.
- The compiler (aCC) provides a callback for exception events;
- GDB can set a breakpoint on this callback and find out what
- exception event has occurred. */
-
-/* The name of the hook to be set to point to the callback function */
-static char HP_ACC_EH_notify_hook[] = "__eh_notify_hook";
-/* The name of the function to be used to set the hook value */
-static char HP_ACC_EH_set_hook_value[] = "__eh_set_hook_value";
-/* The name of the callback function in end.o */
-static char HP_ACC_EH_notify_callback[] = "__d_eh_notify_callback";
-/* Name of function in end.o on which a break is set (called by above) */
-static char HP_ACC_EH_break[] = "__d_eh_break";
-/* Name of flag (in end.o) that enables catching throws */
-static char HP_ACC_EH_catch_throw[] = "__d_eh_catch_throw";
-/* Name of flag (in end.o) that enables catching catching */
-static char HP_ACC_EH_catch_catch[] = "__d_eh_catch_catch";
-/* The enum used by aCC */
-typedef enum
- {
- __EH_NOTIFY_THROW,
- __EH_NOTIFY_CATCH
- }
-__eh_notification;
-
-/* Is exception-handling support available with this executable? */
-static int hp_cxx_exception_support = 0;
-/* Has the initialize function been run? */
-int hp_cxx_exception_support_initialized = 0;
-/* Similar to above, but imported from breakpoint.c -- non-target-specific */
-extern int exception_support_initialized;
-/* Address of __eh_notify_hook */
-static CORE_ADDR eh_notify_hook_addr = 0;
-/* Address of __d_eh_notify_callback */
-static CORE_ADDR eh_notify_callback_addr = 0;
-/* Address of __d_eh_break */
-static CORE_ADDR eh_break_addr = 0;
-/* Address of __d_eh_catch_catch */
-static CORE_ADDR eh_catch_catch_addr = 0;
-/* Address of __d_eh_catch_throw */
-static CORE_ADDR eh_catch_throw_addr = 0;
-/* Sal for __d_eh_break */
-static struct symtab_and_line *break_callback_sal = 0;
-
-/* Code in end.c expects __d_pid to be set in the inferior,
- otherwise __d_eh_notify_callback doesn't bother to call
- __d_eh_break! So we poke the pid into this symbol
- ourselves.
- 0 => success
- 1 => failure */
-int
-setup_d_pid_in_inferior (void)
-{
- CORE_ADDR anaddr;
- struct minimal_symbol *msymbol;
- char buf[4]; /* FIXME 32x64? */
-
- /* Slam the pid of the process into __d_pid; failing is only a warning! */
- msymbol = lookup_minimal_symbol ("__d_pid", NULL, symfile_objfile);
- if (msymbol == NULL)
- {
- warning ("Unable to find __d_pid symbol in object file.");
- warning ("Suggest linking executable with -g (links in /opt/langtools/lib/end.o).");
- return 1;
- }
-
- anaddr = SYMBOL_VALUE_ADDRESS (msymbol);
- store_unsigned_integer (buf, 4, PIDGET (inferior_ptid)); /* FIXME 32x64? */
- if (target_write_memory (anaddr, buf, 4)) /* FIXME 32x64? */
- {
- warning ("Unable to write __d_pid");
- warning ("Suggest linking executable with -g (links in /opt/langtools/lib/end.o).");
- return 1;
- }
- return 0;
-}
-
-/* Initialize exception catchpoint support by looking for the
- necessary hooks/callbacks in end.o, etc., and set the hook value to
- point to the required debug function
-
- Return 0 => failure
- 1 => success */
-
-static int
-initialize_hp_cxx_exception_support (void)
-{
- struct symtabs_and_lines sals;
- struct cleanup *old_chain;
- struct cleanup *canonical_strings_chain = NULL;
- int i;
- char *addr_start;
- char *addr_end = NULL;
- char **canonical = (char **) NULL;
- int thread = -1;
- struct symbol *sym = NULL;
- struct minimal_symbol *msym = NULL;
- struct objfile *objfile;
- asection *shlib_info;
-
- /* Detect and disallow recursion. On HP-UX with aCC, infinite
- recursion is a possibility because finding the hook for exception
- callbacks involves making a call in the inferior, which means
- re-inserting breakpoints which can re-invoke this code */
-
- static int recurse = 0;
- if (recurse > 0)
- {
- hp_cxx_exception_support_initialized = 0;
- exception_support_initialized = 0;
- return 0;
- }
-
- hp_cxx_exception_support = 0;
-
- /* First check if we have seen any HP compiled objects; if not,
- it is very unlikely that HP's idiosyncratic callback mechanism
- for exception handling debug support will be available!
- This will percolate back up to breakpoint.c, where our callers
- will decide to try the g++ exception-handling support instead. */
- if (!hp_som_som_object_present)
- return 0;
-
- /* We have a SOM executable with SOM debug info; find the hooks */
-
- /* First look for the notify hook provided by aCC runtime libs */
- /* If we find this symbol, we conclude that the executable must
- have HP aCC exception support built in. If this symbol is not
- found, even though we're a HP SOM-SOM file, we may have been
- built with some other compiler (not aCC). This results percolates
- back up to our callers in breakpoint.c which can decide to
- try the g++ style of exception support instead.
- If this symbol is found but the other symbols we require are
- not found, there is something weird going on, and g++ support
- should *not* be tried as an alternative.
-
- ASSUMPTION: Only HP aCC code will have __eh_notify_hook defined.
- ASSUMPTION: HP aCC and g++ modules cannot be linked together. */
-
- /* libCsup has this hook; it'll usually be non-debuggable */
- msym = lookup_minimal_symbol (HP_ACC_EH_notify_hook, NULL, NULL);
- if (msym)
- {
- eh_notify_hook_addr = SYMBOL_VALUE_ADDRESS (msym);
- hp_cxx_exception_support = 1;
- }
- else
- {
- warning ("Unable to find exception callback hook (%s).", HP_ACC_EH_notify_hook);
- warning ("Executable may not have been compiled debuggable with HP aCC.");
- warning ("GDB will be unable to intercept exception events.");
- eh_notify_hook_addr = 0;
- hp_cxx_exception_support = 0;
- return 0;
- }
-
- /* Next look for the notify callback routine in end.o */
- /* This is always available in the SOM symbol dictionary if end.o is linked in */
- msym = lookup_minimal_symbol (HP_ACC_EH_notify_callback, NULL, NULL);
- if (msym)
- {
- eh_notify_callback_addr = SYMBOL_VALUE_ADDRESS (msym);
- hp_cxx_exception_support = 1;
- }
- else
- {
- warning ("Unable to find exception callback routine (%s).", HP_ACC_EH_notify_callback);
- warning ("Suggest linking executable with -g (links in /opt/langtools/lib/end.o).");
- warning ("GDB will be unable to intercept exception events.");
- eh_notify_callback_addr = 0;
- return 0;
- }
-
-#ifndef GDB_TARGET_IS_HPPA_20W
- /* Check whether the executable is dynamically linked or archive bound */
- /* With an archive-bound executable we can use the raw addresses we find
- for the callback function, etc. without modification. For an executable
- with shared libraries, we have to do more work to find the plabel, which
- can be the target of a call through $$dyncall from the aCC runtime support
- library (libCsup) which is linked shared by default by aCC. */
- /* This test below was copied from somsolib.c/somread.c. It may not be a very
- reliable one to test that an executable is linked shared. pai/1997-07-18 */
- shlib_info = bfd_get_section_by_name (symfile_objfile->obfd, "$SHLIB_INFO$");
- if (shlib_info && (bfd_section_size (symfile_objfile->obfd, shlib_info) != 0))
- {
- /* The minsym we have has the local code address, but that's not the
- plabel that can be used by an inter-load-module call. */
- /* Find solib handle for main image (which has end.o), and use that
- and the min sym as arguments to __d_shl_get() (which does the equivalent
- of shl_findsym()) to find the plabel. */
-
- args_for_find_stub args;
- static char message[] = "Error while finding exception callback hook:\n";
-
- args.solib_handle = som_solib_get_solib_by_pc (eh_notify_callback_addr);
- args.msym = msym;
- args.return_val = 0;
-
- recurse++;
- catch_errors (cover_find_stub_with_shl_get, &args, message,
- RETURN_MASK_ALL);
- eh_notify_callback_addr = args.return_val;
- recurse--;
-
- exception_catchpoints_are_fragile = 1;
-
- if (!eh_notify_callback_addr)
- {
- /* We can get here either if there is no plabel in the export list
- for the main image, or if something strange happened (?) */
- warning ("Couldn't find a plabel (indirect function label) for the exception callback.");
- warning ("GDB will not be able to intercept exception events.");
- return 0;
- }
- }
- else
- exception_catchpoints_are_fragile = 0;
-#endif
-
- /* Now, look for the breakpointable routine in end.o */
- /* This should also be available in the SOM symbol dict. if end.o linked in */
- msym = lookup_minimal_symbol (HP_ACC_EH_break, NULL, NULL);
- if (msym)
- {
- eh_break_addr = SYMBOL_VALUE_ADDRESS (msym);
- hp_cxx_exception_support = 1;
- }
- else
- {
- warning ("Unable to find exception callback routine to set breakpoint (%s).", HP_ACC_EH_break);
- warning ("Suggest linking executable with -g (link in /opt/langtools/lib/end.o).");
- warning ("GDB will be unable to intercept exception events.");
- eh_break_addr = 0;
- return 0;
- }
-
- /* Next look for the catch enable flag provided in end.o */
- sym = lookup_symbol (HP_ACC_EH_catch_catch, (struct block *) NULL,
- VAR_DOMAIN, 0, (struct symtab **) NULL);
- if (sym) /* sometimes present in debug info */
- {
- eh_catch_catch_addr = SYMBOL_VALUE_ADDRESS (sym);
- hp_cxx_exception_support = 1;
- }
- else
- /* otherwise look in SOM symbol dict. */
- {
- msym = lookup_minimal_symbol (HP_ACC_EH_catch_catch, NULL, NULL);
- if (msym)
- {
- eh_catch_catch_addr = SYMBOL_VALUE_ADDRESS (msym);
- hp_cxx_exception_support = 1;
- }
- else
- {
- warning ("Unable to enable interception of exception catches.");
- warning ("Executable may not have been compiled debuggable with HP aCC.");
- warning ("Suggest linking executable with -g (link in /opt/langtools/lib/end.o).");
- return 0;
- }
- }
-
- /* Next look for the catch enable flag provided end.o */
- sym = lookup_symbol (HP_ACC_EH_catch_catch, (struct block *) NULL,
- VAR_DOMAIN, 0, (struct symtab **) NULL);
- if (sym) /* sometimes present in debug info */
- {
- eh_catch_throw_addr = SYMBOL_VALUE_ADDRESS (sym);
- hp_cxx_exception_support = 1;
- }
- else
- /* otherwise look in SOM symbol dict. */
- {
- msym = lookup_minimal_symbol (HP_ACC_EH_catch_throw, NULL, NULL);
- if (msym)
- {
- eh_catch_throw_addr = SYMBOL_VALUE_ADDRESS (msym);
- hp_cxx_exception_support = 1;
- }
- else
- {
- warning ("Unable to enable interception of exception throws.");
- warning ("Executable may not have been compiled debuggable with HP aCC.");
- warning ("Suggest linking executable with -g (link in /opt/langtools/lib/end.o).");
- return 0;
- }
- }
-
- /* Set the flags */
- hp_cxx_exception_support = 2; /* everything worked so far */
- hp_cxx_exception_support_initialized = 1;
- exception_support_initialized = 1;
-
- return 1;
-}
-
-/* Target operation for enabling or disabling interception of
- exception events.
- KIND is either EX_EVENT_THROW or EX_EVENT_CATCH
- ENABLE is either 0 (disable) or 1 (enable).
- Return value is NULL if no support found;
- -1 if something went wrong,
- or a pointer to a symtab/line struct if the breakpointable
- address was found. */
-
-struct symtab_and_line *
-child_enable_exception_callback (enum exception_event_kind kind, int enable)
-{
- char buf[4];
-
- if (!exception_support_initialized || !hp_cxx_exception_support_initialized)
- if (!initialize_hp_cxx_exception_support ())
- return NULL;
-
- switch (hp_cxx_exception_support)
- {
- case 0:
- /* Assuming no HP support at all */
- return NULL;
- case 1:
- /* HP support should be present, but something went wrong */
- return (struct symtab_and_line *) -1; /* yuck! */
- /* there may be other cases in the future */
- }
-
- /* Set the EH hook to point to the callback routine */
- store_unsigned_integer (buf, 4, enable ? eh_notify_callback_addr : 0); /* FIXME 32x64 problem */
- /* pai: (temp) FIXME should there be a pack operation first? */
- if (target_write_memory (eh_notify_hook_addr, buf, 4)) /* FIXME 32x64 problem */
- {
- warning ("Could not write to target memory for exception event callback.");
- warning ("Interception of exception events may not work.");
- return (struct symtab_and_line *) -1;
- }
- if (enable)
- {
- /* Ensure that __d_pid is set up correctly -- end.c code checks this. :-( */
- if (PIDGET (inferior_ptid) > 0)
- {
- if (setup_d_pid_in_inferior ())
- return (struct symtab_and_line *) -1;
- }
- else
- {
- warning ("Internal error: Invalid inferior pid? Cannot intercept exception events.");
- return (struct symtab_and_line *) -1;
- }
- }
-
- switch (kind)
- {
- case EX_EVENT_THROW:
- store_unsigned_integer (buf, 4, enable ? 1 : 0);
- if (target_write_memory (eh_catch_throw_addr, buf, 4)) /* FIXME 32x64? */
- {
- warning ("Couldn't enable exception throw interception.");
- return (struct symtab_and_line *) -1;
- }
- break;
- case EX_EVENT_CATCH:
- store_unsigned_integer (buf, 4, enable ? 1 : 0);
- if (target_write_memory (eh_catch_catch_addr, buf, 4)) /* FIXME 32x64? */
- {
- warning ("Couldn't enable exception catch interception.");
- return (struct symtab_and_line *) -1;
- }
- break;
- default:
- error ("Request to enable unknown or unsupported exception event.");
- }
-
- /* Copy break address into new sal struct, malloc'ing if needed. */
- if (!break_callback_sal)
- {
- break_callback_sal = (struct symtab_and_line *) xmalloc (sizeof (struct symtab_and_line));
- }
- init_sal (break_callback_sal);
- break_callback_sal->symtab = NULL;
- break_callback_sal->pc = eh_break_addr;
- break_callback_sal->line = 0;
- break_callback_sal->end = eh_break_addr;
-
- return break_callback_sal;
-}
-
-/* Record some information about the current exception event */
-static struct exception_event_record current_ex_event;
-/* Convenience struct */
-static struct symtab_and_line null_symtab_and_line =
-{NULL, 0, 0, 0};
-
-/* Report current exception event. Returns a pointer to a record
- that describes the kind of the event, where it was thrown from,
- and where it will be caught. More information may be reported
- in the future */
-struct exception_event_record *
-child_get_current_exception_event (void)
-{
- CORE_ADDR event_kind;
- CORE_ADDR throw_addr;
- CORE_ADDR catch_addr;
- struct frame_info *fi, *curr_frame;
- int level = 1;
-
- curr_frame = get_current_frame ();
- if (!curr_frame)
- return (struct exception_event_record *) NULL;
-
- /* Go up one frame to __d_eh_notify_callback, because at the
- point when this code is executed, there's garbage in the
- arguments of __d_eh_break. */
- fi = find_relative_frame (curr_frame, &level);
- if (level != 0)
- return (struct exception_event_record *) NULL;
-
- select_frame (fi);
-
- /* Read in the arguments */
- /* __d_eh_notify_callback() is called with 3 arguments:
- 1. event kind catch or throw
- 2. the target address if known
- 3. a flag -- not sure what this is. pai/1997-07-17 */
- event_kind = read_register (ARG0_REGNUM);
- catch_addr = read_register (ARG1_REGNUM);
-
- /* Now go down to a user frame */
- /* For a throw, __d_eh_break is called by
- __d_eh_notify_callback which is called by
- __notify_throw which is called
- from user code.
- For a catch, __d_eh_break is called by
- __d_eh_notify_callback which is called by
- <stackwalking stuff> which is called by
- __throw__<stuff> or __rethrow_<stuff> which is called
- from user code. */
- /* FIXME: Don't use such magic numbers; search for the frames */
- level = (event_kind == EX_EVENT_THROW) ? 3 : 4;
- fi = find_relative_frame (curr_frame, &level);
- if (level != 0)
- return (struct exception_event_record *) NULL;
-
- select_frame (fi);
- throw_addr = get_frame_pc (fi);
-
- /* Go back to original (top) frame */
- select_frame (curr_frame);
-
- current_ex_event.kind = (enum exception_event_kind) event_kind;
- current_ex_event.throw_sal = find_pc_line (throw_addr, 1);
- current_ex_event.catch_sal = find_pc_line (catch_addr, 1);
-
- return &current_ex_event;
-}
-
/* Instead of this nasty cast, add a method pvoid() that prints out a
host VOID data type (remember %p isn't portable). */