[PATCH] D96875: [flang][driver] Add -fdebug-module-writer option

Thu Feb 18 05:52:32 PST 2021

awarzynski added a comment.

Thank you for submitting this @arnamoy10 ! Comments inline.

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Comment at: clang/include/clang/Driver/Options.td:4232-4233
   HelpText<"Use INTEGER(KIND=8) for the result type in size-related intrinsics.">;
+def fdebug_module_writer : Flag<["-"],"fdebug-module-writer">, Group<f_Group>, 
+  HelpText<"Enables showing debug messages while writing module files.">;
 }
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IMO this should be a frontend-only option. Compiler end-users are unlikely to need this in their regular workflows, right?  I recommend moving it [[ https://github.com/llvm/llvm-project/blob/adfd3c7083f9808d145239153c10f72eece485d8/clang/include/clang/Driver/Options.td#L4262-L4272 | here ]].

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Comment at: flang/test/Semantics/mod-file-rewriter.f90:9
+! RUN: %flang-new -fsyntax-only -fdebug-module-writer %p/Inputs/mod-file-unchanged.f90 2>&1 | FileCheck %s --check-prefix CHECK_UNCHANGED
+! RUN: %flang-new -fsyntax-only -fdebug-module-writer %p/Inputs/mod-file-changed.f90 2>&1 | FileCheck %s --check-prefix CHECK_CHANGED

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arnamoy10 wrote:
> tskeith wrote:
> > Why do you need to duplicate these lines? Doesn't it work to use `%flang`?
> `%flang` will unfortunately invoke `f18` currently.
That depends on the value of `FLANG_BUILD_NEW_DRIVER`, which is translated into `include_flang_new_driver_test` [[ https://github.com/llvm/llvm-project/blob/adfd3c7083f9808d145239153c10f72eece485d8/flang/test/lit.cfg.py#L74-L85 | here ]]. I also think that this should work fine with `%flang`.

Also, I suggest that we only have tests with `flang_fc1` and keep this as a frontend-only option.

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D96875/new/

https://reviews.llvm.org/D96875