in reply to Re^8: if Digest::SHA1 loaded Can't load LibXML/LibXML.dll Invalid access to memory location
in thread if Digest::SHA1 loaded Can't load LibXML/LibXML.dll Invalid access to memory location

"dumpbin mydll.dll" will show section names and sizes

I have 2 builds of PLplot.dll - both are the same size (3,327,028 bytes). I have named one of them PLplot_broken.dll, and the other PLplot_ok.dll. They can be obtained from: 
http://www.sisyphusion.tk/junk/PLplot_broken.dll
and
http://www.sisyphusion.tk/junk/PLplot_ok.dll

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Both were built using the same compiler, and against the same plplot static library.
Running 'dumpbin PLplot_broken.dll' and 'dumpbin PLplot_ok.dll produces identical results (except of course, for the file name that is reported): 
Microsoft (R) COFF/PE Dumper Version 7.00.9466
Copyright (C) Microsoft Corporation.  All rights reserved.


Dump of file PLplot_ok.dll

File Type: DLL

  Summary

        1000 .CRT
        B000 .bss
        6000 .data
        1000 .debug_abbrev
        1000 .debug_aranges
       B3000 .debug_info
       1B000 .debug_line
       92000 .debug_loc
        A000 .debug_ranges
        2000 .debug_str
        C000 .edata
       16000 .eh_frame
        2000 .idata
       16000 .rdata
       4E000 .reloc
      10E000 .text
        1000 .tls

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If I use PLplot_ok.dll as the PLplot.dll I get: 
C:\>pmver PDL::Graphics::PLplot
0.61

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If I use PLplot_broken.dll as the PLplot.dll I get: 
C:\>pmver PDL::Graphics::PLplot
Can't load 'C:/MinGW/perl589/site/lib/auto/PDL/Graphics/PLplot/PLplot.
+dll' for module PDL::Graphics::PLplot: load_file:%1 is not a valid Wi
+n32 application at C:/MinGW/perl589/lib/DynaLoader.pm line 226.
 at -e line 1
Compilation failed in require at -e line 1.

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Any advice on how I might be able to come to an understanding of why one is ok, but the other not, would be most welcome.

Cheers,
Rob
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Re^10: if Digest::SHA1 loaded Can't load LibXML/LibXML.dll Invalid access to memory location
by Anonymous Monk on Dec 05, 2012 at 14:34 UTC
[reply]
Re^10: if Digest::SHA1 loaded Can't load LibXML/LibXML.dll Invalid access to memory location
by bulk88 (Priest) on Dec 05, 2012 at 19:01 UTC
    sections /29, /59, and .reloc are different sizes. .text is identical size. The instructions in .text I am pretty sure (didn't look too deeply, using my tools) are identical except for the effects of relocation. The 2 DLLs have different base addresses, and both are i386 and have identical PE headers except for the relocation. Where can I get a copy of libgcc_s_dw2-1.dll? Strawberry perl 5.8.9.5 doesn't have one.

    *Both* files gave me this warning when I used PE Explorer on them.

    " Warning! Section </4> (3) extends beyond the raw file offset of section <.bss> (4)."
[reply]
      Where can I get a copy of libgcc_s_dw2-1.dll?

      I've just uploaded it to here.
      It's a dll that ships with the mingw.org builds of 32-bit gcc. Strawberry's compilers are built by a different vendor.

      Thanks for taking a look.

      Cheers,
      Rob
[reply]
        Both ok and broken loaded correctly without error. Win32::LoadLibrary returns a handle for both and reading that handle as a mem block, the first 2 letters were MZ (dll/exe magic). Can not reproduce.
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