Re: -D ?

[Tom Tromey <tromey at redhat dot com>]

>>>>> "Akos" == akos szalay <akos.szalay@sophos.com> writes:

Akos> What does the -D switch do ?

>From the manual:

    @item -D@var{name}[=@var{value}]
    This option can only be used with @code{--main}.  It defines a system
    property named @var{name} with value @var{value}.  If @var{value} is not
    specified then it defaults to the empty string.  These system properties
    are initialized at the program's startup and can be retrieved at runtime
    using the @code{java.lang.System.getProperty} method.

The manual ought to be online somewhere, but to be honest I've never
checked.

Akos> In the help it says "-D<macro> Define a <macro> with string '1'
Akos> as its value", which is what I need, but when using it, I get an
Akos> error "can't specify '-D' without '--main'.

Yes.  You're reading the definition for C/C++, which is different.
Java doesn't have macros, so that definition of -D makes no sense for gcj.

Akos> I try to compile together java and c code by using JNI (which
Akos> works just fine in the version from 17/12/2001 - in 3.0.4 it
Akos> seems to be broken).  So what does the -D switch do, and what
Akos> should I use instead to define a macro ?

If you're compiling C code you should invoke `gcc'.  If you're
compiling C++ you should invoke `g++'.  Both of these will accept -D
in the way you expect.  gcj should only be used for compiling Java
code (either .java, .class, or resource files with --resource).

Akos> BTW, any estimation on the release of 3.1 ?

Soon, as soon as the critical bugs are fixed.  A prerelease came out
today.

Tom