[PATCH] D52296: [Clang] - Add -fdwarf-fission=split,single option.

[George Rimar via Phabricator via cfe-commits]

grimar added inline comments.


================
Comment at: lib/Driver/ToolChains/Clang.cpp:5889
   const llvm::Triple &T = getToolChain().getTriple();
-  if (Args.hasArg(options::OPT_gsplit_dwarf) &&
+  if ((getDebugFissionKind(D, Args) == DwarfFissionKind::Split) &&
       (T.isOSLinux() || T.isOSFuchsia())) {
----------------
probinson wrote:
> grimar wrote:
> > dblaikie wrote:
> > > Could having more than one call to getDebugFissionKind lead to the error message (for -fdwarf-fission=garbage) being printed multiple times? Or is this call on a distinct/mutually exclusive codepath to the other?
> > I think it should not be possible. Currently, there are 2 inclusions of the `getDebugFissionKind `. One is used for construction clang job,
> > and one is here, it is used to construct an assembler tool job. I do not see a way how it can be printed multiple times.
> > 
> > For example, the following invocation will print it only once:
> > 
> > ```
> > clang main.c -o out.s -S -fdwarf-fission=foo
> > clang-8: error: unsupported argument 'foo' to option 'fdwarf-fission='
> > ```
> The example you give here will not create an assembler job. Try
> `clang main.c -fdwarf-fission=foo -fno-integrated-as` which I think will exercise the path David is asking about.
Oh, I did not know.

Seems the important option to test is `-save-temps`. Seems I have the same result with `-fno-integrated-as`/`-fintegrated-as`,
but with/without `-save-temps` I got:

```
clang main.cpp -fdwarf-fission=foo -o 1.o
clang-8: error: unsupported argument 'foo' to option 'fdwarf-fission='

clang main.cpp -fdwarf-fission=foo -o 1.o -save-temps
clang-8: error: unsupported argument 'foo' to option 'fdwarf-fission='
clang-8: error: unsupported argument 'foo' to option 'fdwarf-fission='
clang-8: error: unsupported argument 'foo' to option 'fdwarf-fission='
clang-8: error: unsupported argument 'foo' to option 'fdwarf-fission='
```

Will fix, thanks!

(The behavior seems weird to me. I would not expect tool will be creating any jobs should happen when the command line is invalid from the start. I am not very familiar with the clang code/logic though to say it wrong).


https://reviews.llvm.org/D52296