I am trying to install FST so I can start using the VST plugins I need for my music production. After spending a lot of time tracking all the dependencies (seems I needed the Dev packages for all the dependencies), when I enter "Make", I get the following result:

I don't understand what the problem is. I downloaded the package at http://joebutton.co.uk/fst/ and followed the instructions, installed the Steinberg SDK and all. I'm using Ubuntu Feisty Fawn. I tried running Make as root, both with Jack running and not, with my Timidity MIDI server running and not, and it always gives the same results. Does anyone have any idea?

From these two lines it seems the compilation does not know where the libpthread.so library is. After checking if you have this library on your system, you can check if the options passed to winegcc include the correct path and library name.
Since it uses pkg-config to locate libraries and their dependencies, you can test from the command line by echoing the winegcc lines themselves. I mean, you can try to do the following:
that is: type echo on the command line and then past exactly the relevant winegcc line from the output of make. In this way all the pkg-config commands will be executed (expanded) and you will see all the option passed to winegcc. If you don't notice anything like
on the resulting command lines, probably you have to edit the Makefile to add the proper location and/or name of the required library. Hope this will help a little.

Thanks!

The library is indeed in my system, in the usr/lib directory. I'm not sure how I can echo the make command, since when I type Make, a huge command appears. It seems to make up 4 or 5 lines, but it looks like it's just one command that's so long that the text wraps around. So I believe it's just one line. I copied that whole thing and tried the echo, like this:
Which resulted in this:
With a straight return to the command prompt, not anything else. So I tried to go on with the next step you suggested, but I can't figure out how to edit the makefile. I suppose I should add the path and filename somewhere in the Libraries section:
But what's the proper syntax? Should it look like this:
? And what about the path to libpthread.so (/usr/lib)? Or should it go somewhere else in the makefile?

The command you echoed is ok: indeeed this is a single long command line that has been wrapped from the terminal. The echo command simply echoes the same line without doing anything but the expansion of the pkg-config "inline" commands.
Here the -lpthread option does not appear! To be sure you can verify also the lines:
that make the compilation of the two wrong object files: jfst.o and vsti.o (the ones for which you got the "undefined symbol" errors).
To edit the make file you can try to add
to some variable in the header (LIBRARIES may be good) or - as alternative - you can leave the Makefile unchanged and define an environment variable called CFLAGS, e.g. by the command
This is because most likely the make process will look for this (and other) variables and add their value as options to the compiler. You will see the differences in the output from make.

To reply to your last questions: the syntax pkg-config --libs libpthread.so is wrong because pkg-config is a utility that look for config files with the .pc extension. These files are named as the application to which they are associated and contain information about includes, library paths, dependencies and so on. Usually they are in /usr/lib/pkgconfig/. You may have a look at "man pkg-config" for details.

Grazie Mille colucix! It worked! I echoed both commands you provided and still didn't have -lpthread in them, so I simply edited the Makefile adding the line you gave. Now I'm getting the "can't load plugin" error. But FST is installed and runs, so I can start looking around for debugging. Thanks again!

Prego! As a final comment, it sounds strange to me that the pthread library is not seen anyway, since it is in a default location. Probably you have to update the library cache. See
for details. You can try (as root)
to see if the library is stored in the current cache. And if not, you can try to update (just for future use). Cheers!