Gfortran offloading reduction error

[Patrick Begou]

Hi,

I'm testing some OpenMP offloading behavior and gfortran 15.2 raise a 
bad behaviour with this small piece of code.

The code tests an array of a simple user defined type with 2 arrays (a 
vector of 3 elements and a matrix of 3x3 elements). The arrays sizes are 
known at compile time.

An array of 10 element is built, values are intialized then they are 
checked on host and on device.

The code works with Nvidia (nvhpc/24.3 on A100 and nvhpc/25.5 on T600), 
Cray Fortran (cce18 on Mi250) or the AMD compiler (on Mi250) but not 
with GCC 15.2 on Nvidia T600 nor with the old GCC OG13 on Nvidia A100 GPU .

In the provided code the reductions (kernels lines 100 or 107) seams to 
always return .true. with gfortran. Changing the tested value (removing 
the minus sign for exemple) do no change the code behaviour.

Built with:

gfortran -c -fopenmp -cpp begou_omp_array_of_types.f90
gfortran begou_omp_array_of_types.o  -fopenmp -cpp -o 
begou_omp_array_of_types.exe

execution shows always:

    on cpu OK
    on gpu OK
Element xx is valid


Patrick
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