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Your Name Here · Guest

Hello all!

It appears to me that the -fPIC option induces a memory leak
in egcs-2.91.66 (apologies for the old version). I was curious if
someone might look this over and make sure I'm not just ignorant.
I'd like to know if this happens on gcc 3.0 or later before I start
complaining on bugzilla or whatever. Very short example follows with
a makefile creating two programs, the first, "leak" should run smoothly
(the second column is relatively constant), while the second "leak"
clearly demonstrates a successively decreasing amount of memory (there's
probably a better way to demonstrate this, but this works for now).
Note the distinction between the class leakr being placed in the same
directory vs. a separate directory.
If you take out "-fpic", then both programs work.
Of course, the original intent was to make a shared library and
then the makefile would be different (I'd be linking with a .a instead
of a .o), but that shouldn't matter, should it?

Thanks for your help,
Andrew

::::::::::::::
leak.cpp
::::::::::::::
#include <iostream>
#include <cmath>
#include "leakr.h"

using namespace std;

int main(void) {
leakr ap;

for(int i=0;i<10000;i++) {
ap.calc_ez("");
if (i%1000==0) {
cout << i << "t" << flush;
system("free | grep "Mem" | awk '{print $4}'");
}
}
return 0;
}
::::::::::::::
leak2.cpp
::::::::::::::
#include #include <cmath>
#include "lib/leakr.h"

using namespace std;

int main(void) {
leakr ap;

for(int i=0;i<10000;i++) {
ap.calc_ez("");
if (i%1000==0) {
cout << i << "t" << flush;
system("free | grep "Mem" | awk '{print $4}'");
}
}
return 0;
}
::::::::::::::
leakr.cpp
::::::::::::::
#include "leakr.h"

using namespace std;

int leakr::calc_ez(std::string stype) {
for(int kk=0;kk<1000;kk++) {
double d=sin(cos(0.5));
}
return 0;

}
::::::::::::::
leakr.h
::::::::::::::
#include #include <string>

class leakr {

public:
leakr() {};

virtual int calc_ez(std::string stype);

};
::::::::::::::
lib/leakr.cpp
::::::::::::::
#include "leakr.h"

using namespace std;

int leakr::calc_ez(std::string stype) {
for(int kk=0;kk<1000;kk++) {
double d=sin(cos(0.5));
}
return 0;

}
::::::::::::::
lib/leakr.h
::::::::::::::
#include #include <string>

class leakr {

public:
leakr() {};

virtual int calc_ez(std::string stype);

};
::::::::::::::
makefile
::::::::::::::
all: leak leak2

leakr.o:
g++ -fpic -c leakr.cpp

leak.o:
g++ -c leak.cpp

leak: leak.o leakr.o
g++ -o leak leak.cpp leakr.cpp

lib/leakr.o:
cd lib; g++ -fpic -c leakr.cpp

leak2.o:
g++ -c leak2.cpp

leak2: leak2.o lib/leakr.o
g++ -o leak2 leak2.o lib/leakr.o

clean:
-rm *.o lib/*.o leak leak2 *~ lib/*~

leak.tar.gz:
tar cvzf leak.tar.gz lib/*.cpp lib/*.h *.cpp *.h makefile

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Raoul Gough · Guest

[email]eknecronzontas (AT) excite (DOT) com[/email] (Your Name Here) writes: