Re: [PATCH] nat/fork-inferior: include linux-ptrace.h

[Pedro Alves <palves@redhat.com>]

On 06/27/2018 03:24 PM, Simon Marchi wrote:
> On 2018-06-25 04:05, Thomas Petazzoni wrote:
>> To decide whether fork() or vfork() should be used, fork-inferior.c
>> uses the following test:
>>
>>   #if !(defined(__UCLIBC__) && defined(HAS_NOMMU))
>>
>> However, HAS_NOMMU is never defined, because it gets defined in
>> linux-ptrace.h, which is not included by fork-inferior.c. Due to this,
>> gdbserver fails to build on noMMU architectures. This commit fixes
>> that by simply including linux-ptrace.h.
>>
>> This bug was introduced by commit
>> 2090129c36c7e582943b7d300968d19b46160d84 ("Share fork_inferior et al
>> with gdbserver"). Indeed, the same fork()/vfork() selection was done,
>> but in another file where linux-ptrace.h was included.
>>
>> Fixes the following build issue:
>>
>> ../nat/fork-inferior.c: In function 'pid_t fork_inferior(const char*,
>> const string&, char**, void (*)(), void (*)(int), void (*)(), const
>> char*, void (*)(const char*, char* const*, char* const*))':
>> ../nat/fork-inferior.c:376:11: error: 'fork' was not declared in this scope
>>      pid = fork ();
>>            ^~~~
>> ../nat/fork-inferior.c:376:11: note: suggested alternative: 'vfork'
>>      pid = fork ();
>>            ^~~~
>>            vfork
>>
>> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
>> ---
>>  gdb/nat/fork-inferior.c | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/gdb/nat/fork-inferior.c b/gdb/nat/fork-inferior.c
>> index 8b59387fa5..05167628a6 100644
>> --- a/gdb/nat/fork-inferior.c
>> +++ b/gdb/nat/fork-inferior.c
>> @@ -26,6 +26,7 @@
>>  #include "common-gdbthread.h"
>>  #include "signals-state-save-restore.h"
>>  #include "gdb_tilde_expand.h"
>> +#include "linux-ptrace.h"
>>  #include <vector>
>>
>>  extern char **environ;
> 
> Hi Thomas,
> 
> fork-inferior.c is also included in native builds for BSDs, AIX, Solaris and Darwin (see gdb/configure.nat).  I am a bit concerned that linux-ptrace.h could use some Linux-specific things, and thus would break the other builds.  However, I built-tested on FreeBSD and it seems fine.  Worst case, we can probably wrap this include in "#ifdef __linux__" if that becomes a problem.

Please don't.  It seems very wrong to me to include this header on other hosts.
It is full of Linux-only details.

Thanks,
Pedro Alves