Two patches queued into the Linux kernel’s build system development tree, kbuild-next, would enable the -fms-extensions compiler argument everywhere for allowing GCC and LLVM/Clang to use the Microsoft C Extensions when compiling the Linux kernel. Being in kbuild-next these patches will likely be submitted for the Linux 6.19 kernel merge window next month but remains to be seen if there will be any last minute objections to this change.
The -fms-extensions compiler option honored by the GNU Compiler Collection and LLVM/Clang allow enabling some non-standard C/C++ constructs used within Microsoft header files and honored by the the Microsoft Visual C/C++ compiler. For Linux kernel development purposes, enabling the Microsoft C Extensions would allow including a tagged struct or union anonymously in another struct/union.
I sense a fork coming
Pedant thought: The thumbnail shows one biting everywhere but the bullet.
it’s time we nibbled the casing and come to terms with bite the bullet, it’s just a bad metaphor.
Time to chew the cartridge?
Would this cause consequences in terms of the project’s independence? Or are these extensions able to be distributed freely?
From what I can see, the GNU Compiler Collection supports this flag, so you can still build it with 100% free software.
Basically, it’s just behavior that doesn’t align with the C standard, but was introduced by MS. Then, GCC added a compiler flag which makes it behave like that, so that you can build code that requires that behavior.
It doesn’t seem to actually be dependent on MS, rather it’s named after them because it emulates the way their compiler works. I hope no Linux maintainers would entertain the idea of making it dependent on a non-free compiler.
The correct answer. It’s just using an extension Microsoft happens to have made, and everything still works fine without it.
Ah, that makes sense. Thanks for the explanation! :)
