[PATCH] D66487: Fix -Wimplicit-fallthrough warnings in regcomp.c

[Nathan Huckleberry via Phabricator via llvm-commits]

Nathan-Huckleberry marked an inline comment as done.
Nathan-Huckleberry added inline comments.


================
Comment at: llvm/lib/Support/regcomp.c:540
 		REQUIRE(!MORE() || !isdigit((uch)PEEK()), REG_BADRPT);
-		/* FALLTHROUGH */
+		__attribute__((fallthrough));
 	default:
----------------
aaron.ballman wrote:
> nickdesaulniers wrote:
> > aaron.ballman wrote:
> > > The macros in Compiler.h should be updated so that this can use `LLVM_FALLTHROUGH` instead to prevent compile errors.
> > ah, right, otherwise we get into situations where older versions of clang (or other bootstrap compilers) that don't have this feature don't understand this attribute
> Yes, as-is this would break everyone building Clang with MSVC (for instance).
I'm having problems including `Compiler.h` from a c file. I can't include a cpp header into a c file.

```
In file included from llvm/llvm-project/llvm/lib/Support/regcomp.c:51:
llvm/llvm-project/llvm/include/llvm/Support/Compiler.h:19:10: fatal error: 'new' file not found
#include <new>
         ^~~~~
```


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D66487/new/

https://reviews.llvm.org/D66487