The zlib unit cannot be compiled.

The zlib unit cannot compile Delphi/Windows SDK/API
Http://www.delphi2007.net/DelphiAPI/html/delphi_20061204173958124.html
[Error] zlib. PAS (222): unsatisfied forward or external Declaration: 'flate _ trees_free'
[Error] zlib. pa( 562): unsatisfied forward or external Declaration: '@ zcalloc'
[Error] zlib. pa( 562): unsatisfied forward or external Declaration: '@ zcfree'
[Error] zlib. pa( 562): unsatisfied forward or external Declaration: '_ z_errmsg'
[Fatal error] uclnmain. PAS (8): cocould not compile used unit 'zlib. pa'

What is going on? Anxious

How did you compile it? What is the specific situation of your zlib location and whether you have joined a project?

In interface, uses zlib,
Add the zlib path to the Environment path,
The search path is added to the project.
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The previous two compilation operations passed, and later compilation failed. Why ?????
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1. Check the zlib. Pas modification date and whether the file has been accidentally modified. (This possibility is relatively small)
2. Check the zlib unit and check the relatedCodeWhether there are changes (if there are version control tools such as CVS and Svn, it will be much easier)

3. Delete the compiled files of the project, such as *. DCU (for example, gexperts's clean directories function is the best)

Then try again to build the project;

Up

Yes, zlib. PAS has been modified, but I haven't compiled the above method yet,

I don't know why. I used zlib. Pas to create a project at home. Everything is OK,
Take zlib. Pas to the company and place it under source \ RTL \ comma,
Overwrite the original zlib file and create a new project
In interface use zlib
During compilation
Procedure inflate_trees_free; external;
This line cannot pass,
And report errors such as those written in the question.

If this is the case, you may need to check which files have been modified in addition to zlib. PAS in the company's development environment.

For example, zlib. Pas uses the three units respectively,
Sysutils, classes;
Zlibconst;

It is best to use the file search function of windows to find out which VCL files have been modified recently.

Sometimes the cause may be very simple, a definition is incorrect, or a semicolon is missing;