[Bug fortran/15149] New: [gfortran] problem computing Pi

[jv244 at cam dot ac dot uk]

Trying to verify the claim in 
http://gcc.gnu.org/ml/fortran/2004-04/msg00203.html
I keep getting (incorrectly) 0.0 as an approximate value for Pi, whereas 
3.14...
is returned using other compilers.

TYPE point_type
 SEQUENCE
 REAL :: pos(2)
END TYPE
INTEGER, PARAMETER :: N=1000000
TYPE(point_type)     :: points(N)
REAL, DIMENSION(2*N) :: scratch
EQUIVALENCE(points,scratch)
CALL RANDOM_NUMBER(scratch)
scratch=2.0*scratch-1.0
count=0
DO i=1,N
  IF (SUM(points(i)%pos**2)<1.0) THEN
     count=count+1
  ENDIF
ENDDO
write(6,*) 4.0*REAL(count)/REAL(N)
END

with the latest version of gfortran, i.e.

gfortran -v mytest.f90
Driving: gfortran -v mytest.f90 -lgfortranbegin -lgfortran -lm -shared-libgcc
Reading specs from /data1/vondele/gcc-g95/bin/../lib/gcc/i686-pc-linux-gnu/3.5-
tree-ssa/specs
Configured with: /data1/vondele/gcc-g95/gcc/configure --
prefix=/data1/vondele/gcc-g95/ --with-gmp-dir=/data1/vondele/gmp-4.1.2/ --
enable-languages=c,f95
Thread model: posix
gcc version 3.5-tree-ssa 20040426 (merged 20040414)
 /data1/vondele/gcc-g95/bin/../libexec/gcc/i686-pc-linux-gnu/3.5-tree-ssa/f951 
mytest.f90 -quiet -dumpbase mytest.f90 -mtune=pentiumpro -auxbase mytest -
version -o /tmp/ccwcrrYe.s
GNU F95 version 3.5-tree-ssa 20040426 (merged 20040414) (i686-pc-linux-gnu)
        compiled by GNU C version 3.5-tree-ssa 20040426 (merged 20040414).
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
 as -V -Qy -o /tmp/ccaWH9Uk.o /tmp/ccwcrrYe.s
GNU assembler version 2.12.90.0.1 (i386-linux) using BFD version 2.12.90.0.1 
20020307 Debian/GNU Linux
 /data1/vondele/gcc-g95/bin/../libexec/gcc/i686-pc-linux-gnu/3.5-tree-
ssa/collect2 --eh-frame-hdr -m elf_i386 -dynamic-linker /lib/ld-
linux.so.2 /usr/lib/crt1.o /usr/lib/crti.o /data1/vondele/gcc-
g95/bin/../lib/gcc/i686-pc-linux-gnu/3.5-tree-ssa/crtbegin.o -
L/data1/vondele/gcc-g95/bin/../lib/gcc/i686-pc-linux-gnu/3.5-tree-ssa -
L/data1/vondele/gcc-g95/bin/../lib/gcc -L/data1/vondele/gcc-g95//lib/gcc/i686-
pc-linux-gnu/3.5-tree-ssa -L/data1/vondele/gcc-g95/bin/../lib/gcc/i686-pc-
linux-gnu/3.5-tree-ssa/../../.. -L/data1/vondele/gcc-g95//lib/gcc/i686-pc-
linux-gnu/3.5-tree-ssa/../../.. /tmp/ccaWH9Uk.o -lgfortranbegin -lgfortran -
lm -lgcc_s -lgcc -lc -lgcc_s -lgcc /data1/vondele/gcc-g95/bin/../lib/gcc/i686-
pc-linux-gnu/3.5-tree-ssa/crtend.o /usr/lib/crtn.o

-- 
           Summary: [gfortran] problem computing Pi
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jv244 at cam dot ac dot uk
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15149