minimal gcc version for jdk/jdk and usage of -Wno-int-in-bool-context flag in HS build

[Baesken, Matthias]

Hi Magnus / Erik  , thanks for explaning !

Best regards, Matthias

> -----Original Message-----
> From: Magnus Ihse Bursie <magnus.ihse.bursie at oracle.com>
> Sent: Donnerstag, 1. November 2018 11:36
> To: Baesken, Matthias <matthias.baesken at sap.com>; Aleksey Shipilev
> <shade at redhat.com>; 'build-dev at openjdk.java.net' <build-
> dev at openjdk.java.net>
> Subject: Re: minimal gcc version for jdk/jdk and usage of -Wno-int-in-bool-
> context flag in HS build
> 
> 
> 
> On 2018-10-31 17:17, Baesken, Matthias wrote:
> > Hi  Aleksey ,  I tried  with  gcc 6.2   not  6.3  maybe this makes a difference .
> >
> > Unfortunately I cannot see  your  exact gcc/g++  compile calls from the
> logfile .
> > Do you have  "-Wall"  set  which seems to be necessary to enable  the
> additional flag ?
> >
> > https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
> >
> > -Wint-in-bool-context
> > Warn for suspicious use of integer values where boolean values are
> expected, such as conditional expressions (?:) using non-boolean integer
> constants in boolean context, like if (a <= b ? 2 : 3).
> > Or left shifting of signed integers in boolean context, like for (a = 0; 1 << a;
> a++);. Likewise for all kinds of multiplications regardless of the data type.
> > This warning is enabled by -Wall.
> 
> Since JDK-8211029, we have -Wall enabled for hotspot on gcc.
> 
> I can only reiterate what Erik says. Gcc, since a long time ago,
> silently ignores -Wno-XXX for XXX that it does not support or
> understand. *However*, if *another* failure occurs, then gcc prints out
> warnings for unknown -Wno-XXX flags as well. So those are just red
> herrings. If you see them, you will also see another error, and that is
> your real problem.
> 
> /Magnus
> 
> >
> >
> > The   configure flag  --with-extra-cflags   is not used by us .
> >
> > Best regards, Matthias
> >
> >
> >