[PATCH] Precheck modification time between source and object file before showing source line

[Taeung Song]

Andrew,

I modified this PATCH as you said like below.
For now, I'll send v2 with the changes.

If you want to change the warning message format again,
please tell me it! :)

diff --git a/binutils/objdump.c b/binutils/objdump.c
index 6ec79b1..1a3f22b 100644
--- a/binutils/objdump.c
+++ b/binutils/objdump.c
@@ -1389,7 +1389,7 @@ try_print_file_open (const char *origname, const 
char *modname)
     If found, add location to print_files linked list.  */

  static struct print_file_list *
-update_source_path (const char *filename, char *objname)
+update_source_path (const char *filename, bfd *abfd)
  {
    struct print_file_list *p;
    const char *fname;
@@ -1398,11 +1398,13 @@ update_source_path (const char *filename, char 
*objname)

    if (stat (filename, &fst) < 0)
      return NULL;
-  else {
-    if (stat (objname, &ost) < 0)
+  else
+  {
+    if (bfd_stat (abfd, &ost) < 0)
        return NULL;
      if (fst.st_mtime > ost.st_mtime)
-      warn (_("Source file is more recent than object file\n"));
+      warn (_("Source file is more recent than object file: %s, %s\n"),
+            filename, bfd_get_filename (abfd));
    }

    p = try_print_file_open (filename, filename);
@@ -1561,7 +1563,7 @@ show_line (bfd *abfd, asection *section, bfd_vma 
addr_offset)
          {
            if (reloc)
              filename = xstrdup (filename);
-          p = update_source_path (filename, bfd_get_filename (abfd));
+          p = update_source_path (filename, abfd);
          }

        if (p != NULL && linenumber != p->last_line)


I tested the warning case after applied v2 as below.

     $ objdump -dlS /home/taeung/workspace/test/a.out
...
   400810:	5d                   	pop    %rbp
   400811:	e9 7a ff ff ff       	jmpq   400790 <register_tm_clones>

0000000000400816 <get_cond_maxprice>:
get_cond_maxprice():
/home/taeung/workspace/test/a.c:26
./objdump: Warning: Source file is more recent than object file: 
/home/taeung/workspace/test/a.c, /home/taeung/workspace/test/a.out
};

unsigned int limited_wgt;

unsigned int get_cond_maxprice(int wgt, struct jewelry *jewelry)
{
   400816:	55                   	push   %rbp
   400817:	48 89 e5             	mov    %rsp,%rbp
...


Thanks,
Taeung

On 03/12/2017 11:07 PM, Taeung Song wrote:
> Hi Andrew,
>
> Sorry for late reply.
>
> On 03/10/2017 07:25 PM, Andrew Burgess wrote:
>> * Taeung Song <treeze.taeung@gmail.com> [2017-03-10 17:50:43 +0900]:
>>
>>> When running 'objdump -dlS',
>>> if source file is more recent than object file,
>>> line numbers can't match printed actual source code lines.
>>> So print a warning message in the above case.
>>>
>>> binutils/ChangeLog:
>>>
>>>     * objdump.c (update_source_path): Check modification time between
>>>     source and object file before opening source file.
>>>     (show_line): Pass additional argument for object file name
>>>     into update_source_path()
>>> ---
>>>  binutils/objdump.c | 14 ++++++++++++--
>>>  1 file changed, 12 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/binutils/objdump.c b/binutils/objdump.c
>>> index 4609858..237ec45 100644
>>> --- a/binutils/objdump.c
>>> +++ b/binutils/objdump.c
>>> @@ -1389,12 +1389,22 @@ try_print_file_open (const char *origname,
>>> const char *modname)
>>>     If found, add location to print_files linked list.  */
>>>
>>>  static struct print_file_list *
>>> -update_source_path (const char *filename)
>>> +update_source_path (const char *filename, char *objname)
>>
>> I wonder if it would be neater to pass the bfd* pointer in here and
>> then use bfd_stat below?
>>
>
> Okey, I'll use bfd_stat instead of just stat in v2 !
>
>>>    struct print_file_list *p;
>>>    const char *fname;
>>> +  struct stat fst, ost;
>>>    int i;
>>>
>>> +  if (stat (filename, &fst) < 0)
>>> +    return NULL;
>>> +  else {
>>
>> The '{' needs to move onto the next line, then re-indent the block below.
>
> I got it.
>
>>> +    if (stat (objname, &ost) < 0)
>>> +      return NULL;
>>> +    if (fst.st_mtime > ost.st_mtime)
>>> +      warn (_("Source file is more recent than object file\n"));
>>
>> Seems like a good thing to warn about.  How about adding the name of
>> the source file and object file to the warning?
>>
>> Thanks,
>> Andrew
>>
>
> I understood!
> What kind of this warning format do you prefer ?
>
> For example, the source file is '/home/taeung/workspace/hello.c' and
> the object file is '/home/taeung/workspace/a.out'
>
>   1) just one line
> objdump: Warning: Source file is more recent than object file:
> '/home/taeung/workspace/hello.c', '/home/taeung/workspace/a.out'
>
>   2) two lines
> objdump: Warning: Source file is more recent than object file:
>   ('/home/taeung/workspace/hello.c', '/home/taeung/workspace/a.out')
>
>   3) show directly the name of source file and object file
> objdump: Warning: '/home/taeung/workspace/hello.c' is more recent than
> '/home/taeung/workspace/a.out'
>
> Thanks,
> Taeung
>
>>> +  }
>>> +
>>>    p = try_print_file_open (filename, filename);
>>>    if (p != NULL)
>>>      return p;
>>> @@ -1551,7 +1561,7 @@ show_line (bfd *abfd, asection *section,
>>> bfd_vma addr_offset)
>>>      {
>>>        if (reloc)
>>>          filename = xstrdup (filename);
>>> -      p = update_source_path (filename);
>>> +      p = update_source_path (filename, bfd_get_filename (abfd));
>>>      }
>>>
>>>        if (p != NULL && linenumber != p->last_line)
>>> --
>>> 2.7.4
>>>