[lazarus] Copmpiler dependency bug ??

[Marc Weustink]

At 13:16 08-04-2000 -0400, Michael A. Hess wrote:
>Marc Weustink wrote:
> >
> > Hi,
> > While addapting the makefiles I ran into the following problem:
> >
> > In the interface unit A uses B
> > In the interface unit B uses C
> > In the implementation unit C uses A
> >
> > When you compile A, unit B and C are created as well. If you compile A
> > again unit B is recompiled, since the checksum for C is changed.
> > This is IMO not correct, nothing is changed.
>
>It shouldn't. If you compile A it used B so it depends on B being
>compiled FIRST. When B tries to compile before A it determines that C
>must be compile FIRST. So first C is compiled then this allows B to be
>compiled which then allows A to be compiled. The lowest on in the chain
>is always compiled first. If you make changes to unit A and try to
>recompile it it will note that neither B or C has changed since A was
>compiled last and will not recompile them.
>
>Now that is at least HOW it should work. If you are seeing something
>different then there is a problem.
>
>If you compile A then the make file should never ask B or C to compile
>since the date check will have determined that they were already
>compiled by A.
>
>What leads you to believe that this isn't working? I'm not say it is or
>isn't or that your analysis isn't correct I just haven't seen this
>problem yet.

I'm not talking about the creation order nor changingfiles nor using make.

As you confirmed, if you compile A, C and B are compiled first. Correct.
If you don't change anything and you recompile A, B and C are still there 
and it shouldn't be necesary to recompile them.

What I see is that unit B is recompiled the second time I compile A.
After that only a is compiled.
Try the example I've attached.

marc:~/fpc/lazarus/examples/test$ ppc386 a
Target OS: Linux for i386
Compiling a.pas
Compiling b.pas
Compiling c.pas
Compiling a.pas
Compiling b.pas
Assembling (pipe) b.s
Assembling (pipe) a.s
Assembling (pipe) c.s
57 Lines compiled, 0.0 sec
marc:~/fpc/lazarus/examples/test$ ppc386 a
Target OS: Linux for i386
Compiling a.pas
Compiling b.pas
Assembling (pipe) b.s
21 Lines compiled, 0.0 sec
marc:~/fpc/lazarus/examples/test$ ppc386 a
Target OS: Linux for i386
Compiling a.pas
6 Lines compiled, 0.0 sec
marc:~/fpc/lazarus/examples/test$

What I try to make clear is as long as this "recompilation" is the case we 
can't create an "indepandent" LCL, IE, a LCL with only compiled units. For 
every project, the compiler wants to rebuild the LCL (and that's something 
we don't want).

Marc