RFR: 8224087: Compile C code for at least C99 Standard compliance

[Erik Joelsson]

Looks even better!

/Erik

On 2019-05-20 17:56, David Holmes wrote:
> Thank you everyone for taking a look at this.
>
> Here is version 2:
>
> http://cr.openjdk.java.net/~dholmes/8224087/webrev.v2/
>
> Changes:
> - set c99 rather than gnu99
> - Volker's change for xlc to match gcc and clang
> - added short note to build doc (can do wiki later)
> - cosmetic change of name to make variable based on other feedback 
> during the C++14 discussion
>
> Thanks,
> David
>
> On 20/05/2019 5:40 pm, David Holmes wrote:
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8224087
>> webrev: http://cr.openjdk.java.net/~dholmes/8224087/webrev/
>>
>> The need to remove a for-loop declaration expression to appease gcc 
>> 4.8 annoyed me enough to investigate setting C99 as our minimum allow 
>> C-language level when compiling. It turned out to be a lot more 
>> complex a situation than I thought due to toolchain quirks. See lots 
>> of details in the bug report.
>>
>> To summarise the changes:
>> - gcc: force to -std=gnu99
>> - clang force to -std=gnu99
>> - Solaris studio - no effective change
>> - Visual Studio - no change
>> - xlc - no effective change (but we use the explicit flag rather than 
>> accepting it as default)
>>
>> I've checked how this works with all the toolchains except xlc as I 
>> have no access to that. Some assistance from someone who can verify 
>> the correctness on xlc would be appreciated.
>>
>> Thanks,
>> David