[flang-commits] [PATCH] D84334: Version information in flang/f18

Wed Jul 22 15:29:15 PDT 2020

coti marked an inline comment as done.
coti added a comment.

Fixed an error in my reply

================
Comment at: flang/tools/f18/f18.cpp:414
+  options.predefinitions.emplace_back("__F18_PATCHLEVEL__", "0");
+  options.predefinitions.emplace_back("__FLANG", "12.0.0");
+  options.predefinitions.emplace_back("__FLANG_MAJOR__", "12");
----------------
coti wrote:
> klausler wrote:
> > coti wrote:
> > > klausler wrote:
> > > > The older flang compiler reportedly defines `__FLANG`.  If so, it might be a bad idea to also define `__FLANG` in this newer flang compiler,; how would conditionally compiled code distinguish one flang compiler from the other?
> > > So I have a question here: what is the rule regarding compatibility between old and new flang? I came across situations where I needed these because I tried to compile software that knew the old flang and used these values.
> > Does that software that you mentioned use `#ifdef __FLANG` or `#if __FLANG`, as opposed to checking the value of the macro?
> This is in SuperLU.
> 
> It looks for all of them but `__FLANG ` only needs to be defined:
> 
>  ```
> #elif defined(__FLANG)
>         PRINT *, 'INFO:compiler[Flang]'
> # define COMPILER_VERSION_MAJOR DEC(__FLANG_MAJOR__)
> # define COMPILER_VERSION_MINOR DEC(__FLANG_MINOR__)
> # if defined(__FLANG_PATCHLEVEL__)
> #  define COMPILER_VERSION_PATCH DEC(__FLANG_PATCHLEVEL__)
> # endif
>  ```
Sorry, not in SuperLU, but in CMake 3.17.0
https://gitlab.kitware.com/cmake/cmake/blob/master/Modules/CMakeFortranCompilerId.F.in

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D84334/new/

https://reviews.llvm.org/D84334