This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [tree-ssa] Remove useless null pointer checks


Jeff Sturm writes:
 > On 31 Jul 2003, Diego Novillo wrote:
 > > On Thu, 2003-07-31 at 12:43, Jeff Sturm wrote:
 > > > On Thu, 31 Jul 2003, Andrew Haley wrote:
 > > > > We need a way to mark such an attribute in Java source.  We don't have
 > > > > an attribute syntax and we want to stay Java compatible.  Stylized
 > > > > comments, perhaps?
 > > >
 > > > I was thinking primarily of library functions like _Jv_AllocObject.  Since
 > > > they are declared in the frontend, we can assign any attributes we like.
 > > >
 > > C++'s new() operator could be similarly marked, right?
 > 
 > Probably.  The two interesting things about "new" memory are that it
 > cannot alias anything and cannot be null.  For the former we could set the
 > "malloc" attribute of the call (though gcj doesn't do that currently).
 > 
 > Would it be worthwhile to express this in GIMPLE, i.e. NEW_EXPR?

But there are many standard library methods that cannot return NULL;
they either return an object reference or throw an exception.  So
NEW_EXPR is too specific.

Andrew.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]