Hi Joost, thank you for your kind response.

Actually, I don't see the point of defining the variable in the for cycle. You're assigning a value to a C variable, which actually has no reference count or implicit disposal; moreover, the Perl interpreter has no clue about what you're going to do with the return value (unless you tell it).

What I'm saying is that your code is equivalent to the following cycle: 

    for (;;) {
        ENTER;
        SAVETMPS;
        eval_pv("1;", TRUE);
        FREETMPS;
        LEAVE;
    }

[download]
which has no explicit handling of the return value of eval_pv.

But I still thank you because your suggestion actually made me think: why do I need PUSHMARK(SP) and SPAGAIN? I removed them and... I had less leakage. (BTW, I'm going to modify my original post to include this enhancement).

Yes, less but not zero leakage. When my program starts, now, it has the following memory footprint (i.e. what you get before the first "read"): 

Name:   embed01
Pid:    13386
FDSize: 256
VmSize:     2696 kB
VmLck:         0 kB
VmRSS:       940 kB
VmData:      256 kB
VmStk:         8 kB
VmExe:       836 kB
VmLib:      1516 kB

[download]
When I let the program go, I notice an increment in VmSize of around 4 kB every million iteration i let go; so, after 4 million iterations, I get: 
Name:   embed01
Pid:    13386
FDSize: 256
VmSize:     2712 kB
VmLck:         0 kB
VmRSS:      1056 kB
VmData:      272 kB
VmStk:         8 kB
VmExe:       836 kB
VmLib:      1516 kB

[download]
that is a quite subtle leak IMHO but still a leak. Note that the memory increase is quite slow and time-linear, i.e. if I stop at 2 million iterations I get 2704 kB or something similar.

This is quite an improvement with respect the previous version, but my question remains more or less the same: where is it leaking? Moreover: if I'll ever actually need PUSHMARK(SP) and SPAGAIN... how will I avoid leakage?

TIA, --Flavio

In reply to Re^2: Bare-bones embedding and memory leakage by polettix
in thread Bare-bones embedding and memory leakage by polettix

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