disabled c99 in Solaris builds

[Kim Barrett]

> On Dec 11, 2018, at 12:27 PM, Erik Joelsson <erik.joelsson at oracle.com> wrote:
> 
> Hello,
> 
> I do not know why this flag was introduced, but it has been there for a long time. In JDK7 it's listed in jdk/make/common/Defs-solaris.gmk:
> 
> #       -xc99=%none     Do NOT allow for c99 extensions to be used.
> #                       e.g. declarations must precede statements
> 
> and was there since the first mercurial change.
> 
> I personally wouldn't mind ditching it.

FWIW, in my in-development patch set for JEP 347
(https://bugs.openjdk.java.net/browse/JDK-8208089)

the -xc99=%none% option has been removed and -std=c99 added (for C
code). (C++14 includes C99 by reference, so I made that change for
consistency in case there were any ABI differences.)

I haven't encountered any problems attributable to that configuration
change.


> /Erik
> 
> On 2018-12-11 08:17, Baesken, Matthias wrote:
>> Hello , it  seems that currently the Solaris  Oracle Studio Build environment is the only one  that explicitly
>> forbids C99 C code  by setting  -xc99=%none .
>> The current Linux/Mac/AIX/Windows build envs had no issues with the coding.
>> 
>> For example I was running into an error with the C variable declaration order issue (small example below) today in my coding.
>> Is this still a wanted behavior ? What was the reason behind setting -xc99=%none , and is  the reason  still valid ?
>> I remember we had issues with C99 compatibility back then when VS2010  was used on Windows, but I think these  days we use VS2013+, is this correct ?
>> 
>> The example program  mixes declarations and "other statements" ,  which needs C99,  I compile with Oracle Studio 12u4 .
>> 
>> /compiler/SS12u4-Oct2017/SUNWspro/bin/cc  vardecl.c -o vardecl
>> 
>> No settings -> works nicely
>> 
>> 
>> - with C99 disabled as OpenJDK does :
>> ----------------------------------------------------------
>> 
>> /compiler/SS12u4-Oct2017/SUNWspro/bin/cc -xc99=%none   vardecl.c -o vardecl
>> "vardecl.c", line 8: warning: declaration can not follow a statement
>> 
>> 
>> - with C99 disabled + errwarn as OpenJDK does :
>> ------------------------------------------------------------------------
>> 
>> /compiler/SS12u4-Oct2017/SUNWspro/bin/cc -xc99=%none  -errwarn=%all  vardecl.c -o vardecl
>> "vardecl.c", line 8: declaration can not follow a statement
>> cc: acomp failed for vardecl.c
>> 
>> example program :
>> ---------------------------------------
>> 
>> bash-3.2$ more vardecl.c
>> #include <stdio.h>
>> 
>> int main(void) {
>>   int a = 0;
>>   printf("a: %d \n", a);
>> 
>>   int b = 1;
>>   printf("b: %d \n", b);
>>   return 0;
>> }
>> 
>> 
>> Best regards, Matthias