RFR: 8033251: Use DWARF debug symbols for Linux 32-bit as default

[Erik Helin]

Hi Coleen,

thanks for having a look at the patch!

On 2014-03-28 17:30, Coleen Phillimore wrote:
>
> I thought you'd be able to remove the DEBUG_BINARIES logic with this
> change.  It appears there are no platforms left that use stabs with
> gcc.

Yeah, I also noticed that this change enables cleanups in the Makefiles. 
However, I think it is better to do these cleanups as a second change 
after this one, what do you think?

On 2014-03-28 17:30, Coleen Phillimore wrote:
> Does this change add -g for saproc, adlc and jsig compilations also?
It seems like saproc uses SA_DEBUG_CFLAGS which only is being set if 
DEBUG_BINARIES=true. If DEBUG_BINARIES is not true, then it seems like 
we don't generate debug symbols (please correct me if I'm wrong).

The above also seems to be the case for libjsig.so.

Looking in make/linux/makefiles/adlc.make it seems like adlc is using -g 
for GCC 3.3 or newer.

Thanks,
Erik

> Coleen
>
> On 3/28/14 12:12 PM, Erik Helin wrote:
>> Hi all,
>>
>> this patch changes the Linux Makefiles to use DWARF as the default
>> debug symbol format for Linux 32-bit instead of STABS. The main
>> arguments for using DWARF are:
>>
>>   - DWARF provides a superior debugging experience compared to STABS.
>>   - STABS support in GCC/GDB is in maintenance mode [0].
>>   - External tools (e.g. perf on Linux) often understands DWARF but not
>>     STABS.
>>   - Compilation on 32-bit Linux can make use of precompiled headers.
>>
>> Webrev:
>> http://cr.openjdk.java.net/~ehelin/8033251/webrev.00/
>>
>> Testing:
>> - Compiling with GCC 4.3.4, GCC 4.7.3 and GCC 4.8.1
>> - JPRT
>>
>> Thanks,
>> Erik
>>
>> [0]: https://sourceware.org/ml/binutils/2013-01/msg00028.html
>