Mirror of the gdb-patches mailing list
 help / color / mirror / Atom feed
From: Tom Tromey <tromey@adacore.com>
To: Simon Marchi <simark@simark.ca>
Cc: Tom Tromey <tromey@adacore.com>,  gdb-patches@sourceware.org
Subject: Re: [PATCH v3 21/29] Share handle_exception
Date: Wed, 15 Apr 2020 13:13:16 -0600	[thread overview]
Message-ID: <87zhbc8svn.fsf@tromey.com> (raw)
In-Reply-To: <214bbace-933a-a99e-1fcd-0956b6b4a5bd@simark.ca> (Simon Marchi's message of "Wed, 15 Apr 2020 13:54:19 -0400")

>>>>> "Simon" == Simon Marchi <simark@simark.ca> writes:

Simon> It helps, but there's still:

Simon>   CXX    nat/windows-nat.o
Simon> /home/smarchi/src/binutils-gdb/gdbserver/../gdb/nat/windows-nat.c: In function ‘windows_nat::handle_exception_result windows_nat::handle_exception(target_waitstatus*, bool)’:
Simon> /home/smarchi/src/binutils-gdb/gdbserver/../gdb/nat/windows-nat.c:214:10: error: ‘find_pc_partial_function’ was not declared in this scope
Simon>   214 |      || (find_pc_partial_function (addr, &fn, NULL, NULL)
Simon>       |          ^~~~~~~~~~~~~~~~~~~~~~~~

Yeah, I realized this quite a while after sending it.

Simon> If we look at gdbserver's version of the function before this change, it didn't have that part,
Simon> so perhaps it should be factored out into a callback, which will reside in gdb/windows-nat.c.

Yep, please try this.

Tom

commit 3cb8f05b1e897a617e499edc54c9fc5cf456634c
Author: Tom Tromey <tromey@adacore.com>
Date:   Wed Apr 15 13:11:23 2020 -0600

    Fix Cygwin gdb build
    
    Simon pointed out that the windows-nat sharing series broke the Cygwin
    build.  This patch fixes the problem, by moving the Cygwin-specific
    code to a new handler function.  This approach is taken because this
    code calls find_pc_partial_function, which isn't available in
    gdbserver.
    
    gdb/ChangeLog
    2020-04-15  Tom Tromey  <tromey@adacore.com>
    
            * windows-nat.c (windows_nat::handle_access_violation): New
            function.
            * nat/windows-nat.h (handle_access_violation): Declare.
            * nat/windows-nat.c (handle_exception): Move Cygwin code to
            windows-nat.c.  Call handle_access_violation.
    
    gdbserver/ChangeLog
    2020-04-15  Tom Tromey  <tromey@adacore.com>
    
            * win32-low.cc (windows_nat::handle_access_violation): New
            function.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index b0a535a624f..f6a15d1482c 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,11 @@
+2020-04-15  Tom Tromey  <tromey@adacore.com>
+
+	* windows-nat.c (windows_nat::handle_access_violation): New
+	function.
+	* nat/windows-nat.h (handle_access_violation): Declare.
+	* nat/windows-nat.c (handle_exception): Move Cygwin code to
+	windows-nat.c.  Call handle_access_violation.
+
 2020-04-15  Tom Tromey  <tromey@adacore.com>
 
 	* windows-nat.c (DEBUG_EXEC, DEBUG_EVENTS, DEBUG_MEM)
diff --git a/gdb/nat/windows-nat.c b/gdb/nat/windows-nat.c
index cd7c1d177c6..8c2092a51d7 100644
--- a/gdb/nat/windows-nat.c
+++ b/gdb/nat/windows-nat.c
@@ -184,26 +184,8 @@ handle_exception (struct target_waitstatus *ourstatus, bool debug_exceptions)
     case EXCEPTION_ACCESS_VIOLATION:
       DEBUG_EXCEPTION_SIMPLE ("EXCEPTION_ACCESS_VIOLATION");
       ourstatus->value.sig = GDB_SIGNAL_SEGV;
-#ifdef __CYGWIN__
-      {
-	/* See if the access violation happened within the cygwin DLL
-	   itself.  Cygwin uses a kind of exception handling to deal
-	   with passed-in invalid addresses.  gdb should not treat
-	   these as real SEGVs since they will be silently handled by
-	   cygwin.  A real SEGV will (theoretically) be caught by
-	   cygwin later in the process and will be sent as a
-	   cygwin-specific-signal.  So, ignore SEGVs if they show up
-	   within the text segment of the DLL itself.  */
-	const char *fn;
-	CORE_ADDR addr = (CORE_ADDR) (uintptr_t) rec->ExceptionAddress;
-
-	if ((!cygwin_exceptions && (addr >= cygwin_load_start
-				    && addr < cygwin_load_end))
-	    || (find_pc_partial_function (addr, &fn, NULL, NULL)
-		&& startswith (fn, "KERNEL32!IsBad")))
-	  return HANDLE_EXCEPTION_UNHANDLED;
-      }
-#endif
+      if (handle_access_violation (rec))
+	return HANDLE_EXCEPTION_UNHANDLED;
       break;
     case STATUS_STACK_OVERFLOW:
       DEBUG_EXCEPTION_SIMPLE ("STATUS_STACK_OVERFLOW");
diff --git a/gdb/nat/windows-nat.h b/gdb/nat/windows-nat.h
index aea1519672d..8d0fa9bd216 100644
--- a/gdb/nat/windows-nat.h
+++ b/gdb/nat/windows-nat.h
@@ -157,6 +157,13 @@ extern void handle_unload_dll ();
 
 extern bool handle_ms_vc_exception (const EXCEPTION_RECORD *rec);
 
+/* When EXCEPTION_ACCESS_VIOLATION is processed, we give the embedding
+   application a chance to change it to be considered "unhandled".
+   This function must be supplied by the embedding application.  If it
+   returns true, then the exception is "unhandled".  */
+
+extern bool handle_access_violation (const EXCEPTION_RECORD *rec);
+
 
 /* Currently executing process */
 extern HANDLE current_process_handle;
diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index e82e58ec1f2..b857f82eb89 100644
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -1230,6 +1230,31 @@ windows_nat::handle_ms_vc_exception (const EXCEPTION_RECORD *rec)
   return false;
 }
 
+/* See nat/windows-nat.h.  */
+
+bool
+windows_nat::handle_access_violation (const EXCEPTION_RECORD *rec)
+{
+#ifdef __CYGWIN__
+  /* See if the access violation happened within the cygwin DLL
+     itself.  Cygwin uses a kind of exception handling to deal with
+     passed-in invalid addresses.  gdb should not treat these as real
+     SEGVs since they will be silently handled by cygwin.  A real SEGV
+     will (theoretically) be caught by cygwin later in the process and
+     will be sent as a cygwin-specific-signal.  So, ignore SEGVs if
+     they show up within the text segment of the DLL itself.  */
+  const char *fn;
+  CORE_ADDR addr = (CORE_ADDR) (uintptr_t) rec->ExceptionAddress;
+
+  if ((!cygwin_exceptions && (addr >= cygwin_load_start
+			      && addr < cygwin_load_end))
+      || (find_pc_partial_function (addr, &fn, NULL, NULL)
+	  && startswith (fn, "KERNEL32!IsBad")))
+    return true;
+#endif
+  return false;
+}
+
 /* Resume thread specified by ID, or all artificially suspended
    threads, if we are continuing execution.  KILLED non-zero means we
    have killed the inferior, so we should ignore weird errors due to
diff --git a/gdbserver/ChangeLog b/gdbserver/ChangeLog
index 2b381455ed7..d22b6b2daef 100644
--- a/gdbserver/ChangeLog
+++ b/gdbserver/ChangeLog
@@ -1,3 +1,8 @@
+2020-04-15  Tom Tromey  <tromey@adacore.com>
+
+	* win32-low.cc (windows_nat::handle_access_violation): New
+	function.
+
 2020-04-13  Tom Tromey  <tom@tromey.com>
 
 	* server.h (gdb_fildes_t): Remove typedef.
diff --git a/gdbserver/win32-low.cc b/gdbserver/win32-low.cc
index e1226b4b0db..41348dd77d4 100644
--- a/gdbserver/win32-low.cc
+++ b/gdbserver/win32-low.cc
@@ -1198,6 +1198,14 @@ windows_nat::handle_ms_vc_exception (const EXCEPTION_RECORD *rec)
   return false;
 }
 
+/* See nat/windows-nat.h.  */
+
+bool
+windows_nat::handle_access_violation (const EXCEPTION_RECORD *rec)
+{
+  return false;
+}
+
 /* A helper function that will, if needed, set
    'stopped_at_software_breakpoint' on the thread and adjust the
    PC.  */


  reply	other threads:[~2020-04-15 19:13 UTC|newest]

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-13 19:08 [PATCH v3 00/29] Windows code sharing + bug fix Tom Tromey
2020-03-13 19:08 ` [PATCH v3 01/29] Remove the "next" field from windows_thread_info Tom Tromey
2020-03-13 19:08 ` [PATCH v3 02/29] Rename win32_thread_info to windows_thread_info Tom Tromey
2020-03-13 19:08 ` [PATCH v3 03/29] Rename windows_thread_info::id to "tid" Tom Tromey
2020-03-13 19:08 ` [PATCH v3 04/29] Share windows_thread_info between gdb and gdbserver Tom Tromey
2020-03-13 19:08 ` [PATCH v3 05/29] Use new and delete for windows_thread_info Tom Tromey
2020-03-13 19:08 ` [PATCH v3 06/29] Change two windows_thread_info members to "bool" Tom Tromey
2020-03-13 19:08 ` [PATCH v3 07/29] Make windows_thread_info::name a unique_xmalloc_ptr Tom Tromey
2020-03-13 19:08 ` [PATCH v3 08/29] Use lwp, not tid, for Windows thread id Tom Tromey
2020-03-13 19:08 ` [PATCH v3 09/29] Share Windows thread-suspend and -resume code Tom Tromey
2020-03-13 19:08 ` [PATCH v3 10/29] Change type of argument to windows-nat.c:thread_rec Tom Tromey
2020-03-13 19:08 ` [PATCH v3 11/29] Handle pending stops from the Windows kernel Tom Tromey
2020-03-13 19:08 ` [PATCH v3 12/29] Call CloseHandle from ~windows_thread_info Tom Tromey
2020-03-13 19:08 ` [PATCH v3 13/29] Wrap shared windows-nat code in windows_nat namespace Tom Tromey
2020-03-13 19:08 ` [PATCH v3 14/29] Share thread_rec between gdb and gdbserver Tom Tromey
2020-03-13 19:08 ` [PATCH v3 15/29] Share get_image_name " Tom Tromey
2020-03-13 19:08 ` [PATCH v3 16/29] Share some Windows-related globals Tom Tromey
2020-03-13 19:08 ` [PATCH v3 17/29] Normalize handle_output_debug_string API Tom Tromey
2020-03-13 19:08 ` [PATCH v3 18/29] Fix up complaints.h for namespace use Tom Tromey
2020-03-13 19:08 ` [PATCH v3 19/29] Share handle_load_dll and handle_unload_dll declarations Tom Tromey
2020-03-13 19:08 ` [PATCH v3 20/29] Remove some globals from windows-nat.c Tom Tromey
2020-03-13 19:08 ` [PATCH v3 21/29] Share handle_exception Tom Tromey
2020-04-15 15:27   ` Simon Marchi
2020-04-15 16:54     ` Tom Tromey
2020-04-15 17:54       ` Simon Marchi
2020-04-15 19:13         ` Tom Tromey [this message]
2020-04-16  0:52           ` Simon Marchi
2020-03-13 19:08 ` [PATCH v3 22/29] Share some inferior-related Windows code Tom Tromey
2020-03-13 19:08 ` [PATCH v3 23/29] Introduce fetch_pending_stop Tom Tromey
2020-03-13 19:08 ` [PATCH v3 24/29] Move wait_for_debug_event to nat/windows-nat.c Tom Tromey
2020-03-13 19:08 ` [PATCH v3 25/29] Make last_wait_event static Tom Tromey
2020-03-13 19:08 ` [PATCH v3 26/29] Add read_pc / write_pc support to win32-low Tom Tromey
2020-03-13 19:08 ` [PATCH v3 27/29] Introduce win32_target_ops::decr_pc_after_break Tom Tromey
2020-03-13 19:08 ` [PATCH v3 28/29] Implement stopped_by_sw_breakpoint for Windows gdbserver Tom Tromey
2020-03-13 19:08 ` [PATCH v3 29/29] Add pending stop support to gdbserver's Windows port Tom Tromey
2020-04-16  1:11   ` [pushed] gdbserver: fix format string warning in win32-low.cc (was: Re: [PATCH v3 29/29] Add pending stop support to gdbserver's Windows port) Simon Marchi
2020-04-08 20:33 ` [PATCH v3 00/29] Windows code sharing + bug fix Tom Tromey
2020-04-08 22:17   ` Hannes Domani
2020-04-09  2:49     ` Tom Tromey
2020-04-09 14:57       ` Jon Turney
2020-04-09 15:08         ` Hannes Domani
2020-04-09 17:54         ` Tom Tromey

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87zhbc8svn.fsf@tromey.com \
    --to=tromey@adacore.com \
    --cc=gdb-patches@sourceware.org \
    --cc=simark@simark.ca \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox