[Bug fortran/40508] New: memory leak in internal write of gfortran

[alain dot hebert at polymtl dot ca]

alain-heberts-macbook-pro:~ alainhebert$ gfortran -v
Using built-in specs.
Target: i386-apple-darwin8.10.1
Configured with: /tmp/gfortran-20090604/ibin/../gcc/configure
--prefix=/usr/local/gfortran --enable-languages=c,fortran
--with-gmp=/tmp/gfortran-20090604/gfortran_libs --enable-bootstrap
Thread model: posix
gcc version 4.5.0 20090604 (experimental) [trunk revision 148180] (GCC) 

There is a memory leak in the latest build of gfortran. This leak is related to
the internal write operation. The bug occurs when there is no memory left (it
can be long...).

Here is the code:
      character hmg1*52,hmg2*52
      integer idata(13)
      hmg1='1234567890123456789012345678901234567890123456789012'
      read(hmg1,'(13A4)') (idata(ii),ii=1,13)
      do i=1,100
         do j=1,10000000
            write(hmg2,'(13A4)') (idata(ii),ii=1,13)
         enddo
         print *,i,hmg2
      enddo
      print *,'everything OK'
      stop
      end

Here is the output:
(cut...)
          21 1234567890123456789012345678901234567890123456789012
          22 1234567890123456789012345678901234567890123456789012
a.out(96109) malloc: *** mmap(size=2097152) failed (error code=12)
*** error: can't allocate region
*** set a breakpoint in malloc_error_break to debug
Operating system error: Cannot allocate memory
Memory allocation failed


-- 
           Summary: memory leak in internal write of gfortran
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: critical
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: alain dot hebert at polymtl dot ca


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40508