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STLport �

Did anyone successfully use this with GCC 3.3? I unpacked it and tried: g++ -I/tmp/stlport but I get a dozen compiler errors (related to includes).

I was interestd in seeing if it will generate smaller code than using the standard GCC STL. Check this out:

// #include

int main () { std::vector v1, v2; for(int i = 0; i < 20; i++) v1.push_back(i); v2.insert(v2.end(), v1.begin(), v1.end()); return 0; }

% g++ -Os -fno-exceptions -fno-rtti && strip a.out && ls -l a.out -rwxr-xr-x 1 duff admin 67816 13 Feb 20:20 a.out

% g++ -Os -fno-exceptions -fno-rtti -Imystl && strip a.out && ls -l a.out -rwxr-xr-x 1 duff admin 9516 13 Feb 20:21 a.out

In the second line I add the mystl include directory, which contains a minimal stl replacement I wrote myself. So why is the executable 66 KiB when mine is only 9 KiB? I think it has to do with exceptions, even though I disable them, I think they are still enabled when using (some) standard library components.

Also, I do not know if the extra 57 KiB is a one-time add-on.

That’d be something interesting to know. If it’s one-time, then 57K is no big deal. If you get 57K included with every templated class you use, than that’s Bad.

The chunk of code seems to stem from stdlibc++ and is a one-time add-on – if I use std::string only (and not std::vector) the executable is about the same size (67 KiB), but other parts of the standard library also add to the executable, like iostream, something as simple as cout « “Hello world” « endl; amounts to 360 KiB.

In my experience, STLport is a very heavy library, and it’s very challenging to get just the one class you want without inadvertently including a bizillion other (unnecessary, at least to you) classes. This has to do with the very structured approach the STL uses for prefix / postfix / global includes. Try running just the preprocessor (sorry… I forget exactly what the switch is) and see how much stuff gets included. You’ll probably be surprised… I certainly was! I ended up dumping STLport in favor of writing the one or two classes I actually used. That kept the executable size much more reasonable (down to about 1.4MB rather than 11MB!)


** -E is the gcc switch to send preprocessed output to stdout. You’ll need to remove -o from the command line.**

You can use -M to get a list of ‘dependencies’ (i.e. all includes) or -save-temps to let it keep the preprocessed file. But I do not understand your findings, including dozen of headers should not increase executable size, as the headers only declare classes – first when you use these, will your executable grow.