[flang] Long compile time with large array constructor

[DanielCChen]

Consider the following code

  PROGRAM main
  IMPLICIT NONE

  INTEGER(2), PARAMETER :: I2Max=32767
  INTEGER(2), PARAMETER :: I2Min=-32768

  TYPE :: DT0
  END TYPE

  INTEGER, TARGET  :: I

  TYPE(DT0), TARGET  :: I1Arr(I2Min:I2Max)=(/(DT0(),I=I2Min, I2Max)/)
  END

Flang took long time to compile it.
All ifort, gfortran and XLF used much less time.

[llvmbot]

@llvm/issue-subscribers-flang-frontend

Author: Daniel Chen (DanielCChen)

Consider the following code ``` PROGRAM main IMPLICIT NONE

INTEGER(2), PARAMETER :: I2Max=32767
INTEGER(2), PARAMETER :: I2Min=-32768

TYPE :: DT0
END TYPE

INTEGER, TARGET :: I

TYPE(DT0), TARGET :: I1Arr(I2Min:I2Max)=(/(DT0(),I=I2Min, I2Max)/)
END

Flang took long time to compile it.
All ifort, gfortran and XLF used much less time.

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