[dcc32 Error] PasVulkan.Compression.LZMA.pas(3686): E2065 Unsatisfied forward or external declaration: 'C_LzmaDecode'

[JohnHutch123]

In current download, this function has not been fully defined.

[JohnHutch123]

Is it because HasLZMADec is currently defined? I change line 3680 from // - {$undef HasLZMADec} to {$undef HasLZMADec} and this compiles OK.

[BeRo1985]

Yes, that is most likely related to HasLZMADec.

HasLZMADec is only supposed to be defined when a matching precompiled lzmadec_*.o object file is linked for the current TargetOS + TargetCPU combination.

For example:

• Linux + x86_64 uses lzma_c/lzmadec_linux_x86_64.o
• Windows + x86_64 uses lzma_c\lzmadec_windows_x86_64.o
• Android + aarch64 uses lzma_c/lzmadec_android_aarch64.o

If HasLZMADec is defined, the unit expects the external C function C_LzmaDecode to be provided by one of these object files. If the object file is missing, not found by the compiler, or incompatible with the selected target CPU/OS, Delphi/FPC will report the unsatisfied external declaration.

When you manually change:

// -{$undef HasLZMADec}

to:

{$undef HasLZMADec}

you force the unit to use the pure-Pascal LZMA decoder instead, so the external C symbol is no longer needed. That is why it compiles for you.

However, that line is intended only as a manual fallback/debug override, not as the normal fix.

Please check:

1. Which compiler and which version of that compiler are you using?
2. Which target OS and target CPU are you compiling for?
3. Is the corresponding lzma_c/lzmadec_*.o file present in your local checkout?
4. Did you clone the repository normally, or did you download/extract only part of it?

The .o files should be included in the repository. If your target combination is not one of the currently listed combinations, then HasLZMADec should not be defined and the pure-Pascal decoder should be used automatically.

[JohnHutch123]

1. Delphi 12 compiler dcc32290.dll
2. Windows 11 64bit and 32bit on Intel CPU
3. In the folder D:\X1\PasVulkan\src\lzma_c the files lzmadec_windows_x86_32.o and lzmadec_windows_x86_64.o are present. These should be OK yes
4. I downloaded the full version via the zip option and unpacked locally replacing the older set