gdb/mi: New commands to catch C++ exceptions
authorAndrew Burgess <andrew.burgess@embecosm.com>
Wed, 8 May 2019 18:01:36 +0000 (19:01 +0100)
committerAndrew Burgess <andrew.burgess@embecosm.com>
Sat, 15 Jun 2019 22:22:22 +0000 (23:22 +0100)
commit30056ea04ae3ecd828e2a06e12e6f174ae6659c9
tree0241b9853191c5363b2e5089b81ff95413df17c6
parentec8e2b6d3051f0b4b2a8eee9917898e95046c62f
gdb/mi: New commands to catch C++ exceptions

Adds some MI commands to catch C++ exceptions.  The new commands are
-catch-throw, -catch-rethrow, and -catch-catch, these all correspond
to the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.

Each MI command takes two optional arguments, '-t' has the effect of
calling 'tcatch' instead of 'catch', for example:

   (gdb)
   -catch-throw -t

Is the same as:

   (gdb) tcatch throw

There is also a '-r REGEXP' argument that can supply a regexp to match
against the exception type, so:

   (gdb)
   -catch-catch -r PATTERN

Is the same as:

   (gdb) catch catch PATTERN

The change in print_mention_exception_catchpoint might seem a little
strange; changing the output from using ui_out::field_int and
ui_out::text to using  ui_out::message.

The print_mention_exception_catchpoint is used as the 'print_mention'
method for the exception catchpoint breakpoint object.  Most of the
other 'print_mention' methods (see breakpoint.c) use either
printf_filtered, of ui_out::message.  Using field_int was causing an
unexpected field to be added to the MI output.  Here's the output
without the change in print_mention_exception_catchpoint:

    (gdb)
    -catch-throw
    ^done,bkptno="1",bkpt={number="1",type="breakpoint",disp="keep",
                           enabled="y",addr="0x00000000004006c0",
                           what="exception throw",catch-type="throw",
                           thread-groups=["i1"],times="0"}

Notice the breakpoint number appears in both the 'bkptno' field, and
the 'number' field within the 'bkpt' tuple.  Here's the output with
the change in print_mention_exception_catchpoint:

    (gdb)
    -catch-throw
    ^done,bkpt={number="1",type="breakpoint",disp="keep",
                enabled="y",addr="0x00000000004006c0",
                what="exception throw",catch-type="throw",
                thread-groups=["i1"],times="0"}

gdb/ChangeLog:

* NEWS: Mention new MI commands.
* break-catch-throw.c (enum exception_event_kind): Move to
breakpoint.h.
(print_mention_exception_catchpoint): Output text as a single
message.
(catch_exception_command_1): Rename to...
(catch_exception_event): ...this, make non-static, update header
command, and change some parameter types.
(catch_catch_command): Update for changes to
catch_exception_command_1.
(catch_throw_command): Likewise.
(catch_rethrow_command): Likewise.
* breakpoint.c (enum exception_event_kind): Delete.
* breakpoint.h (enum exception_event_kind): Moved here from
break-catch-throw.c.
(catch_exception_event): Declare.
* mi/mi-cmd-catch.c (mi_cmd_catch_exception_event): New function.
(mi_cmd_catch_throw): New function.
(mi_cmd_catch_rethrow): New function.
(mi_cmd_catch_catch): New function.
* mi/mi-cmds.c (mi_cmds): Add 'catch-throw', 'catch-rethrow', and
'catch-catch' entries.
* mi/mi-cmds.h (mi_cmd_catch_throw): Declare.
(mi_cmd_catch_rethrow): Declare.
(mi_cmd_catch_catch): Declare.

gdb/doc/ChangeLog:

* gdb.texinfo (GDB/MI Catchpoint Commands): Add menu entry to new
node.
(C++ Exception GDB/MI Catchpoint Commands): New node to describe
new MI commands.

gdb/testsuite/ChangeLog:

* gdb.mi/mi-catch-cpp-exceptions.cc: New file.
* gdb.mi/mi-catch-cpp-exceptions.exp: New file.
* lib/mi-support.exp (mi_expect_stop): Handle 'exception-caught'
as a stop reason.
14 files changed:
gdb/ChangeLog
gdb/NEWS
gdb/break-catch-throw.c
gdb/breakpoint.c
gdb/breakpoint.h
gdb/doc/ChangeLog
gdb/doc/gdb.texinfo
gdb/mi/mi-cmd-catch.c
gdb/mi/mi-cmds.c
gdb/mi/mi-cmds.h
gdb/testsuite/ChangeLog
gdb/testsuite/gdb.mi/mi-catch-cpp-exceptions.cc [new file with mode: 0644]
gdb/testsuite/gdb.mi/mi-catch-cpp-exceptions.exp [new file with mode: 0644]
gdb/testsuite/lib/mi-support.exp