Re^14: if Digest::SHA1 loaded Can't load LibXML/LibXML.dll Invalid access to memory location

[syphilis]

rebasing seems to have fixed it

Pardon the dumb question ... but how does one do this rebasing ?
There's a few (native Win32, not Cygwin) dll's that I'd like to try this on, but I don't understand how to go about it. (A step-by-step guide would be handy.)

Cheers,
Rob

[Anonymous Monk]

update: ok, step by step
• perl Makefile.PL
• dmake test :) and you notice this error pops up
• if you know which dll it is , edit MAKEFILE LDDLFLAGS add   -Wl,--image-base=0x70000000 and  dmake test again (0x70000000 is default rebase address)

and I'm pooped :)

See Re^3: if Digest::SHA1 loaded Can't load LibXML/LibXML.dll Invalid access to memory location, Re^11: if Digest::SHA1 loaded Can't load LibXML/LibXML.dll Invalid access to memory location

one way is specify the base by adding   -Wl,--image-base=0x70000000 to LDDLFLAGS , when doing Makefile dance

This works well if you trigger the error during the test suite like I did

Another way (i've not tried) is using msdn rebase

or editbin.exe /REBASE

or http://cygwin.wikia.com/wiki/Rebaseall

If you got mingw.org you can  mingw-get install msys-rebase and you'll need  mingw-get install msys-dash for rebaseall (its a 224 line shell script)

I don't know where to get the sources, rebase -V doesn't say, I guess cygwin someplace I already posted before http://www.tishler.net/jason/software/rebase/

http://gmod.org/wiki/GBrowse_Cygwin_HOWTO#Rebaseall

I guess strawberry / citrusperl ought to package rebase.exe and a rebaseall.pl to go along with it

I don't remember now, but I've either read something about a way to have -enable-auto-image-base keep a database of image bases/ranges, so it issues a non conflicting imagebase/range (a free space)

or I thought about it/or patching MakeMaker (or CBuilder whatever) to do the same (keeping a database of image bases/ranges, and replace -enable-auto-image-base with -Wl,--image-base= ) for pre-vista operating systems

but the issue is kinda rare , I've only encountered it less than 6 times in many years, always on a perl install with ~ 1040 cpan distributions :) but only 200-400 dlls

so I suppose PAR-ed up rebaseall.pl packing rebase.exe ought to suffice, if we FAQ up the issue adequately, so folks know what to do :)

If citrusperl offered more binary packages for download (ala ppm), only one guy would have to rebaseall before releasing :)

[Anonymous Monk]

http://perldoc.perl.org/perlcygwin.html#*-rebase-errors-on-fork-or-system mentions a perlrebase that comes with cygwin, http://code.google.com/p/cygwin-rurban/source/browse/trunk/release/perl/perlrebase, https://code.google.com/p/cygwin-rurban/source/browse/trunk/release/perl/build_common, this one uses bin/sh, but particular to cygwin perl

But at least its clear from this one writing one of these shouldn't be hard :)

findrule $installprefix -file -name *.dll | grep -v "rebase\.exe$|msys\S+\.dll$|cyg\S+\.dll" > $tempfile

pskill perl

rebase -T $tempfile -v -s

update: reini discusses makemaker rebase database Re: perlrebase, is there no better way?

So this is more common on cygwin, but should be solvable from makemaker by keeping a database ( without killing perl

update: oh hey , perlrebase came with mingw-get, naturally its for msys-perl not strawberry and alikes :)

[syphilis]

if you know which dll it is , edit MAKEFILE LDDLFLAGS add -Wl,--image-base=0x70000000 and dmake test again (0x70000000 is default rebase address)

Excellent !! That fixes the problem I have with 32-bit perls and PDL::Graphics::PLplot (when PDL::Graphics::PLplot is built as part of the PDL build).

However, it doesn't help with 64-bit perls.
Could it be that the 0x70000000 needs to be a different value on 64-bit perls ?

Note: With 32-bit perls the dll fails to load, with an error message stating that the dll is not a valid Win32 application.
With 64-bit perls the dll also fails to load, but the error message is a little different, claiming an "Invalid access to memory location". After amending the Makefile as per suggested, PDL::Graphics::PLplot *does* get rebuilt (as expected), but the failure and error message remain unchanged.

Cheers,
Rob

[bulk88]

Tried a newer GCC or the other Mingw build (org or w64)?

Invalid access to memory location usually means DllMain did a segfault and Windows caught that exception, and unloaded the DLL, so the LoadLibrary failed.

[Anonymous Monk]

Could it be that the 0x70000000 needs to be a different value on 64-bit perls ?

Probably not, but I have read in one of those rebase links that rebas-ing should be done @ install time for least conflicts, so you should get more info, check for ImageBase conflicts for all dll's involved (even those in %WINDIR% )

Also try depends.exe Ctrl+O perl.exe , F7 ...foo.pl to see a LoadLibrary trace, maybe you'll see something new, but so far it sounds like the same thing I saw