RE: cygwin/gfortran 4.3 install error?

["Art Lazanoff" <art at parrotbyte dot com>]

Thanks to both of you for your suggestions. I managed to compile and
install gfortran. After this, the cygwin version runs the first test
case reasonably well (correct results, respectable times). Got a bit
better throughput on the make on a dual CPU using make -j 2.

Art

Here's my matmul example. The hand written examples are triple loops
doing a matrix multiply. The intrinsic matmul is the third case.
Arithmetic is 64-bit reals. Problem size is (1000,2000) times
(2000,1000).



art@brahms ~/Fortran/MATMUL
$ gfortran -O3 -msse3 -mtune=i686 -o matmul_g matmul.f90

art@brahms ~/Fortran/MATMUL
$ ./matmul_g
 kind real, integer =            8           4
 lenx, leny =         1000        2000
loc(a) =            1AFF610
loc(b) =             BBD210
loc(c) =            2A41A10
loc(c1) =            41C010
loc(c2) =           31E2C10
 hand written time (sec) =    3.125000
 hand written time (sec), i/j loops inverted =    13.07800
 matmul       time (sec) =    3.266001
 result difference at:     1     1 407F5874120437D9 407F5874120437D4
STOP mismatch

The above mismatch isn't significant.

Here's an Intel v10 run using the same source file:

art@brahms ~/Fortran/MATMUL
$ ./matmul.10
 kind real, integer =            8           4
 lenx, leny =         1000        2000
loc(a) =          14009B140
loc(b) =          140FDD540
loc(c) =          141F1F940
loc(c1) =         1426C0B40
loc(c2) =         142E61D40
 hand written time (sec) =    2.765625
 hand written time (sec), i/j loops inverted =   0.7500000
 matmul       time (sec) =   0.7968750

So, gfortran's timing results are respectable.

For reference:

art@brahms ~/Fortran/MATMUL
$ uname -a
CYGWIN_NT-5.2-WOW64 brahms 1.5.24(0.156/4/2) 2007-01-31 10:57 i686
Cygwin

art@brahms ~/Fortran/MATMUL
$ which gfortran
/usr/local/bin/gfortran

art@brahms ~/Fortran/MATMUL
$ ls -lt /usr/local/bin/gfortran
-rwxr-xr-x 2 art None 372230 Apr 25 22:46 /usr/local/bin/gfortran

art@brahms ~/Fortran/MATMUL
$ gfortran -v
Using built-in specs.
Target: i686-pc-cygwin
Configured with: ./configure
Thread model: single
gcc version 4.1.2