Re: loading DLLs created with Cygwin into Sun JDK

["Marcus G. Daniels" <mgd at santafe dot edu>]

> Interesting -- if I add the -Xmx256m flag to `java', my test case 
> works too.


The cause is the fixed `cygwin_shared_address' (set to 0xa000000 in 
winsup/cygwin/shared_info.h).  What happens with Sun JVM loads of 
Cygwin-dependent DLLs is that chunk of virtual memory gets claimed by 
the JVM, and then `open_shared' (in winsup/cygwin/shared.cc) defaults to 
a second MapViewOfFileEx after failing in its attempt to map the fixed 
address.  The second MapViewOfFileEx attempt has a comment that says 
"Probably win95, so try without specifying the address", which doesn't 
seem to be desirable in this case. 

When I rebuilt the Cygwin DLL using 0x20000000 the load of my set of 
DLLs work fine (without the -Xmx256m flag, which was presumably just 
pushing VM allocation blocks around).

Incidentally, does anyone know of a Windows application that can be used 
to see the VM maps in a given process.
(Like in Linux, with /proc/PID/maps?)


--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/