[patch, Fortran] Implement -fexternal-blas64, PR 121161

[Thomas Koenig]

Am 18.09.25 um 19:02 schrieb H.J. Lu:
> FAIL: gfortran.dg/matmul_blas_3.f90   -O   scan-tree-dump-not original
> "integer\\(kind=4\\)"

Hm... would

! { dg-require-effective-target lp64 }

be the right way to fix this?

Best regards

	Thomas