Re: MI problem

[Andrew STUBBS <andrew.stubbs@st.com>]

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Daniel Jacobowitz wrote:
> The interesting question isn't where it gets switched, but where we're
> expecting the wrong contents.  If we're accessing uiout.data->buffer
> then we must have reached mi_out_put.  So where from, and how did we
> get there without switching the global uiout back to MI's? 
> mi_cmd_interpreter_exec ought to be doing that on the way out.

This is the backtrace from the core dump file:

#0  0x0805a220 in ui_file_put (file=0x19, write=0x80863f8 <do_write>, 
dest=0xa030f18)
     at ../../src/gdb/ui-file.c:192
#1  0x0808642a in mi_out_put (uiout=0xa028b90, stream=0xa030f18)
     at ../../src/gdb/mi/mi-out.c:376
#2  0x0808adc9 in mi_load_progress (section_name=0xa11f79f ".init", 
sent_so_far=54,
     total_section=54, total_sent=54, grand_total=523177) at 
../../src/gdb/mi/mi-main.c:1402
#3  0x080c4857 in load_section_callback (abfd=0xa0a5278, asec=0x36, 
data=0xbfffb930)
     at ../../src/gdb/symfile.c:1597
#4  0x0818c69d in bfd_map_over_sections (abfd=0xa0a5278,
     operation=0x80c4670 <load_section_callback>, user_storage=0xbfffb930)
     at ../../src/bfd/section.c:1226
#5  0x080c4a17 in generic_load (args=0xbfffb930 "", from_tty=1) at 
../../src/gdb/symfile.c:1670
#6  0x080edf1f in target_load (arg=0xa0322b0 
"/home/afra/users/stubbsa/os21test-microdev",
     from_tty=1) at ../../src/gdb/target.c:268

mi_load_progress is actually called through the function pointer 
deprecated_show_load_progress.

The problem appears to be that the program is finding it's way into the 
MI through deprecated_show_load_progress when uiout is not set as expected.

The problem only occurs in -i=mi (no number) and -i=mi1 because 
mi_load_progress does not do anything in other versions. Strangely -i=mi 
is supposed to be the same as -i=mi2, but it isn't in this respect.

I attach a patch which fixes both the crash and the inconsistency. I 
have tested it and got no unexpected failures. Of course I doubt the 
testsuite covers this feature ...

OK? I would like to see this issued fixed in 6.4 also.

Andrew Stubbs

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2005-11-17  Andrew Stubbs  <andrew.stubbs@st.com>

	* mi/mi-main.c (mi_load_progress): Don't do anything for -i=mi.
	Ensure the use of mi1 uiout for the duration of the function.

Index: src/gdb/mi/mi-main.c
===================================================================
--- src.orig/gdb/mi/mi-main.c	2005-06-13 23:21:57.000000000 +0100
+++ src/gdb/mi/mi-main.c	2005-11-17 18:58:45.000000000 +0000
@@ -1365,11 +1365,17 @@ mi_load_progress (const char *section_na
   static struct timeval last_update;
   static char *previous_sect_name = NULL;
   int new_section;
+  struct ui_out *saved_uiout;
 
-  if (!current_interp_named_p (INTERP_MI)
-      && !current_interp_named_p (INTERP_MI1))
+  if (!current_interp_named_p (INTERP_MI1))
     return;
 
+  /* This function is called through deprecated_show_load_progress
+     which means uiout may not be correct.  Fix it for the duration
+     of this function.  */
+  saved_uiout = uiout;
+  uiout = mi_out_new (1);
+
   update_threshold.tv_sec = 0;
   update_threshold.tv_usec = 500000;
   gettimeofday (&time_now, NULL);
@@ -1424,6 +1430,9 @@ mi_load_progress (const char *section_na
       fputs_unfiltered ("\n", raw_stdout);
       gdb_flush (raw_stdout);
     }
+
+  xfree (uiout);
+  uiout = saved_uiout;
 }
 
 void