co_reduce
的标准示例命令( https://gcc.gnu.org/onlinedocs/gfortran/CO_005fREDUCE.html#CO_005fREDUCE )似乎不起作用。使用 np
运行示例处理器应该返回 Product value
的 np
!。第一个图像的值以一种看似随机的方式被破坏:
18:10 rditldmt $ caf co_reduce_example.f08 -o co_reduce_example
18:10 rditldmt $ cafrun -np 4 ./co_reduce_example
Number of images = 4
value [ 1 ] is 1690042368
value [ 2 ] is 2
value [ 3 ] is 3
value [ 4 ] is 4
Product value = 1690042368
Expected value = num_images()!
2! = 2, 3! = 6, 4! = 24, ...
与
np = 4
, 预期答案 = 24;计算出的答案 = 1690042368。示例的检测版本,
co_reduce_example.f08
,如下:program co_reduce_example
implicit none
integer :: value[ * ]
integer :: k
value = this_image ( )
call co_reduce ( value, result_image = 1, operator = myProd )
if ( this_image ( ) == 1 ) then
write ( * , '( "Number of images = ", g0 )' ) num_images ( )
do k = 1, num_images ( )
write ( * , '( 2( a, i0 ) )' ) 'value [ ', k, ' ] is ', value [ k ]
end do
write ( * , '( "Product value = ", g0 )' ) value ! prints num_images() factorial
write ( * , 100 )
end if
100 format ( "Expected value = num_images()!", /, " 2! = 2, 3! = 6, 4! = 24, ..." )
contains
pure function myProd ( a, b ) result ( rslt )
integer, value :: a, b
integer :: rslt
rslt = a * b
end function myProd
end program co_reduce_example
如何更正代码?
Coarray Fortran 版本:
17:50 rditldmt $ cafrun -v
OpenCoarrays Coarray Fortran Executable Launcher (caf version 1.3.6)
Copyright (C) 2015-2016 Sourcery, Inc.
OpenCoarrays comes with NO WARRANTY, to the extent permitted by law.
You may redistribute copies of OpenCoarrays under the terms of the
BSD 3-Clause License. For more information about these matters, see
the file named LICENSE.
Gfortran 版本:
17:54 rditldmt $ gfortran -v
Using built-in specs.
COLLECT_GCC=gfortran
COLLECT_LTO_WRAPPER=/opt/local/libexec/gcc/x86_64-apple-darwin15/6.0.0/lto-wrapper
Target: x86_64-apple-darwin15
Configured with: /opt/local/var/macports/build/_opt_mports_dports_lang_gcc6/gcc6/work/gcc-6-20160327/configure --prefix=/opt/local --build=x86_64-apple-darwin15 --enable-languages=c,c++,objc,obj-c++,lto,fortran,java --libdir=/opt/local/lib/gcc6 --includedir=/opt/local/include/gcc6 --infodir=/opt/local/share/info --mandir=/opt/local/share/man --datarootdir=/opt/local/share/gcc-6 --with-local-prefix=/opt/local --with-system-zlib --disable-nls --program-suffix=-mp-6 --with-gxx-include-dir=/opt/local/include/gcc6/c++/ --with-gmp=/opt/local --with-mpfr=/opt/local --with-mpc=/opt/local --with-isl=/opt/local --enable-stage1-checking --disable-multilib --enable-lto --enable-libstdcxx-time --with-as=/opt/local/bin/as --with-ld=/opt/local/bin/ld --with-ar=/opt/local/bin/ar --with-bugurl=https://trac.macports.org/newticket --with-pkgversion='MacPorts gcc6 6-20160327_0'
Thread model: posix
gcc version 6.0.0 20160327 (experimental) (MacPorts gcc6 6-20160327_0)
最佳答案
再次编辑:
您是对的,这是 GFortran 和/或 OpenCoarrays 中的错误,而不是您的代码。关注:https://github.com/sourceryinstitute/opencoarrays/issues/172
我们正在将@dantopa 的代码添加到我们的回归测试中,并希望在 GFortran 7.x 版本之前解决这个问题......一旦它被修复,我会尽量记住更新这个问题。
作为解决方法,请替换 value
属性与 intent(in)
通过更改 value
解决了问题归因于 intent(in)
为 pure function myProd()
.我不确定这是否是 GFortran 实现和/或处理 value
中的错误。属性,并且 IMO 编译器应该发出警告/错误(至少通过我阅读 MRC 的“现代 Fortran 解释”,第 117 页,ii)“必须声明伪参数的意图,除非它是过程或指针,这个意图必须是 in
在函数的情况下')。此外,需要修复 co_reduce 的 GFortran 示例。
关于gcc - 带有 co_reduce 的 Fortran coarray 异常,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/36658286/