Re: [PATCH] Remove <stdint.h> from <sys/sdt.h>

[Chung-Lin Tang <cltang at codesourcery dot com>]

On 2014/10/21 10:29 PM, Josh Stone wrote:
> On 10/21/2014 05:09 AM, Chung-Lin Tang wrote:
>> Hi,
>> We're in the process of considering adding the <sys/sdt.h> header during
>> the build of a full toolchain, which will allow the enabling of
>> SystemTap probes in some target libraries (e.g. glibc).
>>
>> There's a small problem that I'm encountering:  we're configuring glibc
>> with --enable-systemtap, but the configure tests tries a test compile
>> with <sys/sdt.h> before we even have glibc (headers) installed, a small
>> circular dependency actually.
> 
> That is a nice ordering problem indeed...
> 
>> I'm guessing the [u]int(8/16/32)_t types were probably historically used
>> in the <sys/sdt.h> header, but as of currently I see no need of
>> <stdint.h> in there. May I suggest to simply remove the #include?  (I've
>> attached the one-liner patch to be clear)
> 
> I'm trying to see why we had that even historically, and I'm not sure.
> As of now, the only thing I see is __CHAR_BIT__, which is builtin by
> gcc.  Roland also mentioned a while ago that we might remove stdint.h:
> https://lists.fedoraproject.org/pipermail/devel/2011-January/147999.html
> 
> The only risk is that someone may have come to depend on this indirect
> inclusion, but any such user really ought to include stdint.h directly.
> 
> Have you tried the testsuite with that line removed?

I tried 'make installcheck' on a x86_64 machine. I see no regressions
before/after removing #include <stdint.h>  (actually I saw a single
FAIL->PASS in systemtap.samples/tcptest.stp, though I doubt it's because
of this change)

Thanks,
Chung-Lin