Re: [PATCH] PR gdb/21164: maint print {symbols,msymbols,psymbols} without args crash

[Sergio Durigan Junior <sergiodj@redhat.com>]

On Wednesday, February 15 2017, Pedro Alves wrote:

> On 02/15/2017 08:15 PM, Sergio Durigan Junior wrote:
>
>> This patch fixes that.  OK to apply?
>
> Can you add some tests for this, please?

How about this?

Thanks

-- 
Sergio
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commit acd6597d63b2501588318466cd308701d09a58f3
Author: Sergio Durigan Junior <sergiodj@redhat.com>
Date:   Wed Feb 15 15:08:19 2017 -0500

    PR gdb/21164: maint print {symbols,msymbols,psymbols} without args crash
    
    Hi,
    
    This is a fix for PR gdb/21164.  The problem started to happen after:
    
     commit 34c41c681f4a0a0dfe0405c7d2aecf458520557a
     Author:     Doug Evans <xdje42@gmail.com>
     AuthorDate: Mon Dec 19 08:33:46 2016 -0800
    
        New syntax for mt print symbols,msymbols,psymbols.
    
    This change introduced new syntax for the mentioned commands, and
    improved the parsing of arguments by using 'gdb_buildargv'.  However,
    it is necessary to check if the argv being built is not NULL, which
    can happen if the user doesn't provide any arguments to these
    commands.
    
    This patch fixes that.  OK to apply?
    
    gdb/ChangeLog:
    2017-02-15  Sergio Durigan Junior  <sergiodj@redhat.com>
    
            PR gdb/21164
            * psymtab.c (maintenance_print_psymbols): Verify if 'argv' is not
            NULL before using it.
            * symmisc.c (maintenance_print_symbols): Likewise.
            (maintenance_print_msymbols): Likewise.
    
    gdb/testsuite/ChangeLog:
    
    gdb/ChangeLog:
    2017-02-15  Sergio Durigan Junior  <sergiodj@redhat.com>
    
            PR gdb/21164
            * gdb.base/maint.exp: Add testcases for when the commands do
            not have arguments.

diff --git a/gdb/psymtab.c b/gdb/psymtab.c
index 1fad8a0..6e42bc5 100644
--- a/gdb/psymtab.c
+++ b/gdb/psymtab.c
@@ -1926,7 +1926,7 @@ maintenance_print_psymbols (char *args, int from_tty)
   argv = gdb_buildargv (args);
   cleanups = make_cleanup_freeargv (argv);
 
-  for (i = 0; argv[i] != NULL; ++i)
+  for (i = 0; argv != NULL && argv[i] != NULL; ++i)
     {
       if (strcmp (argv[i], "-pc") == 0)
 	{
@@ -1967,7 +1967,7 @@ maintenance_print_psymbols (char *args, int from_tty)
 
   stdio_file arg_outfile;
 
-  if (argv[outfile_idx] != NULL)
+  if (argv != NULL && argv[outfile_idx] != NULL)
     {
       char *outfile_name;
 
diff --git a/gdb/symmisc.c b/gdb/symmisc.c
index 07d571a..ab50570 100644
--- a/gdb/symmisc.c
+++ b/gdb/symmisc.c
@@ -418,7 +418,7 @@ maintenance_print_symbols (char *args, int from_tty)
   argv = gdb_buildargv (args);
   cleanups = make_cleanup_freeargv (argv);
 
-  for (i = 0; argv[i] != NULL; ++i)
+  for (i = 0; argv != NULL && argv[i] != NULL; ++i)
     {
       if (strcmp (argv[i], "-pc") == 0)
 	{
@@ -459,7 +459,7 @@ maintenance_print_symbols (char *args, int from_tty)
 
   stdio_file arg_outfile;
 
-  if (argv[outfile_idx] != NULL)
+  if (argv != NULL && argv[outfile_idx] != NULL)
     {
       char *outfile_name;
 
@@ -721,7 +721,7 @@ maintenance_print_msymbols (char *args, int from_tty)
   argv = gdb_buildargv (args);
   cleanups = make_cleanup_freeargv (argv);
 
-  for (i = 0; argv[i] != NULL; ++i)
+  for (i = 0; argv != NULL && argv[i] != NULL; ++i)
     {
       if (strcmp (argv[i], "-objfile") == 0)
 	{
@@ -747,7 +747,7 @@ maintenance_print_msymbols (char *args, int from_tty)
 
   stdio_file arg_outfile;
 
-  if (argv[outfile_idx] != NULL)
+  if (argv != NULL && argv[outfile_idx] != NULL)
     {
       char *outfile_name;
 
diff --git a/gdb/testsuite/gdb.base/maint.exp b/gdb/testsuite/gdb.base/maint.exp
index 2853508..b87cbfc 100644
--- a/gdb/testsuite/gdb.base/maint.exp
+++ b/gdb/testsuite/gdb.base/maint.exp
@@ -561,6 +561,14 @@ gdb_expect {
 
 #set timeout $oldtimeout
 
+# Testing that the commands work without an argument.  For this test,
+# we don't need an inferior loaded/running.
+# See PR gdb/21164.
+gdb_exit
+gdb_start
+gdb_test_no_output "maint print symbols"
+gdb_test_no_output "maint print msymbols"
+gdb_test_no_output "maint print psymbols"
 
 gdb_exit
 return 0