Mailing-List: contact cygwin-help@sourceware.cygnus.com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@sources.redhat.com Delivered-To: mailing list cygwin@sources.redhat.com Date: Tue, 18 Sep 2001 22:53:36 -0400 From: Christopher Faylor To: cygwin@cygwin.com Subject: Re: [BUG] cygwin-1.3.3-2 -- making auto-import dlls Message-ID: <20010918225336.G8924@redhat.com> Reply-To: cygwin@cygwin.com Mail-Followup-To: cygwin@cygwin.com References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.3.21i On Wed, Sep 19, 2001 at 12:47:32PM +1000, Robert Collins wrote: > > >> -----Original Message----- >> From: Charles Wilson [mailto:cwilson@ece.gatech.edu] >> > Solution: don't use auto-image-base. The overhead from relocation is >> > quite low, why not let windows just do its thing. >> >> >> Okay, suppose I have 5 dll's that are all based at the default, >> 0x10000000. I start an exe that depends on those 5, so at >> startup time >> they all get relocated to (random) address in my exe's address space. >> Then cygwin1.dll is loaded. But the random addresses chosen for the >> relocation for the first 5 dlls MAY or may NOT conflict with >> cygwin1.dll's *fixed* location. >> >> Boom (sometimes). >> >> How is this better than the current "boom (sometimes)" >> behavior? What >> am I missing? > >AFAIK Relocated .dll's will never push a .dll with a different base >address out of the way. I.E. For that set of .dll's > >the program will get it's address 0x10000000, cygwin1.dll get's its base >address, and the 5 .dll's get 5 other random address's. > >How is it better? With a .dll that conflicts with cygwin1.dll, it's boom >(everytime) :]. Just in case anyone knows how to do this: If I could *reserve* but not allocate a fixed amount of memory for the cygwin heap on DLL load, this would fix the problem. I could conceivably add another 512K of allocated memory to the end of every cygwin DLL load but that just didn't seem right. I played around with a lot of ld script file settings trying to achieve this effect but I could never do it. I wouldn't be surprised that Windows doesn't allow actually it because the concept requires a sophisticated run time loader. cgf -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Bug reporting: http://cygwin.com/bugs.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/