llvm-project/flang/documentation
Tim Keith 08c7d570d3 [flang] Add options to control IMPLICIT NONE
Add `-fimplicit-none-type-always` to treat each specification-part
like it has `IMPLICIT NONE`. This is helpful for enforcing good Fortran
programming practices. We might consider something similar for
`IMPLICIT NONE(EXTERNAL)` as well.

Add `-fimplicit-none-type-never` to ignore occurrences of `IMPLICIT NONE`
and `IMPLICIT NONE(TYPE)`. This is to handle cases like the one below,
which violates the standard but it accepted by some compilers:
```
subroutine s(a, n)
  implicit none
  real :: a(n)
  integer :: n
end
```

Differential Revision: https://reviews.llvm.org/D85363
2020-08-06 06:48:01 -07:00
..
ArrayComposition.md
BijectiveInternalNameUniquing.md
C++17.md
C++style.md
Calls.md
Character.md
ControlFlowGraph.md
Directives.md
Extensions.md [flang] Add options to control IMPLICIT NONE 2020-08-06 06:48:01 -07:00
FortranForCProgrammers.md
FortranIR.md
IORuntimeInternals.md
ImplementingASemanticCheck.md
Intrinsics.md [flang] Make 'num_images()' intrinsic 2020-07-07 12:31:10 -07:00
LabelResolution.md
ModFiles.md
OpenMP-4.5-grammar.txt
OpenMP-semantics.md
OptionComparison.md
Overview.md
ParserCombinators.md
Parsing.md
Preprocessing.md
PullRequestChecklist.md
RuntimeDescriptor.md
Semantics.md
f2018-grammar.txt
flang-c-style.el