[binutils-gdb] gdb: remove local extern declaration of cli_styling

[Simon Marchi <simark at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=f64eea3a594042c9cf499b17b5b166276275a051

commit f64eea3a594042c9cf499b17b5b166276275a051
Author: Simon Marchi <simon.marchi@polymtl.ca>
Date:   Wed Sep 18 13:33:33 2019 -0400

    gdb: remove local extern declaration of cli_styling
    
    Following the int -> bool conversion of boolean options (commit
    491144b5e21b ("Change boolean options to bool instead of int")), I see
    this ASAN error:
    
      ==357543==ERROR: AddressSanitizer: global-buffer-overflow on address 0x55555b25d440 at pc 0x5555583ce9e1 bp 0x7fffffffd390 sp 0x7fffffffd380
      READ of size 4 at 0x55555b25d440 thread T0
          #0 0x5555583ce9e0 in term_cli_styling /home/simark/src/binutils-gdb/gdb/ui-file.c:111
          #1 0x5555583cf8b0 in stdio_file::can_emit_style_escape() /home/simark/src/binutils-gdb/gdb/ui-file.c:308
          #2 0x5555584450d2 in set_output_style /home/simark/src/binutils-gdb/gdb/utils.c:1442
          #3 0x5555584491af in fprintf_styled(ui_file*, ui_file_style const&, char const*, ...) /home/simark/src/binutils-gdb/gdb/utils.c:2143
          #4 0x5555582fa13c in print_gdb_version(ui_file*, bool) /home/simark/src/binutils-gdb/gdb/top.c:1339
          #5 0x555557b723ab in captured_main_1 /home/simark/src/binutils-gdb/gdb/main.c:981
          #6 0x555557b7353b in captured_main /home/simark/src/binutils-gdb/gdb/main.c:1172
          #7 0x555557b735d0 in gdb_main(captured_main_args*) /home/simark/src/binutils-gdb/gdb/main.c:1197
          #8 0x55555700a53d in main /home/simark/src/binutils-gdb/gdb/gdb.c:32
          #9 0x7ffff64c9ee2 in __libc_start_main (/usr/lib/libc.so.6+0x26ee2)
          #10 0x55555700a30d in _start (/home/simark/build/binutils-gdb/gdb/gdb+0x1ab630d)
    
      0x55555b25d441 is located 0 bytes to the right of global variable 'cli_styling' defined in '/home/simark/src/binutils-gdb/gdb/cli/cli-style.c:31:6' (0x55555b25d440) of size 1
    
    The reason of this is that we have this declaration of cli_styling in cli/cli-style.h:
    
      extern bool cli_styling;
    
    but ui-file.c uses its  own local declaration:
    
      extern int cli_styling;
    
    Because of that, the code in ui-file.c thinks the variable is 4 bytes
    long, when it is actually 1 byte long, so the generated code reads past
    the variable.
    
    Fix it by removing the declaration and making ui-file.c include
    cli/cli-style.h.
    
    gdb/ChangeLog:
    
    	* ui-file.c: Include cli/cli-style.h.
    	(term_cli_styling): Remove cli_styling declaration.

Diff:
---
 gdb/ChangeLog | 5 +++++
 gdb/ui-file.c | 3 +--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 421b26a..796ade3 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2019-09-18  Simon Marchi  <simon.marchi@polymtl.ca>
+
+	* ui-file.c: Include cli/cli-style.h.
+	(term_cli_styling): Remove cli_styling declaration.
+
 2019-09-18  Alan Modra  <amodra@gmail.com>
 
 	* arm-tdep.c (arm_record_special_symbol): Update bfd_get_section
diff --git a/gdb/ui-file.c b/gdb/ui-file.c
index 042b13c..71b74bb 100644
--- a/gdb/ui-file.c
+++ b/gdb/ui-file.c
@@ -24,6 +24,7 @@
 #include "gdb_obstack.h"
 #include "gdb_select.h"
 #include "gdbsupport/filestuff.h"
+#include "cli/cli-style.h"
 
 null_file null_stream;
 
@@ -106,8 +107,6 @@ ui_file_isatty (struct ui_file *file)
 static bool
 term_cli_styling ()
 {
-  extern int cli_styling;
-
   if (!cli_styling)
     return false;