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Comment by nknight | Hacker News Reader

You really shouldn't be using terms like "regular gcc" or "real gcc", they don't mean what you seem to think they do. GCC is a modular system specifically to provide for things like LLVM-GCC. LLVM-GCC takes the same form as other GCC back-ends for other platforms. i386 has a GCC backend, ARM has a GCC backend, IA64, MIPS, SPARC... Which of these do you nominate to be "real gcc"?

The only measure by which llvm-gcc is not "real" is that it's not included in the core gcc distribution.

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Point taken. But when llvm-gcc doesn't compile the code that every other instance of gcc found on modern platforms does, it's hard to argue that it's the same thing.

Edit -- the llvm-gcc project doesn't seem to share your opinion of the project as being "just another back-end". They certainly don't claim that it's fully compatible, only that it supports "many" features, "most" options, "a number of" extensions:

"Being derived from the GNU Compiler Collection, llvm-gcc has many of gcc's features and accepts most of gcc's options. It handles a number of gcc's extensions to the C programming language."

http://llvm.org/cmds/llvmgcc.html

It's just a tradeoff. LVM offers certain benefits, at the expense of being completely full featured.

This is SOP for GCC backends. Not all platforms support all GCC features. And if you really think there aren't problems building the same code across the various official GCC backends, you're not paying attention. Ask the Linux kernel guys about GCC's code generation oddities.

"And if you really think there aren't problems building the same code across the various official GCC backends, you're not paying attention. Ask the Linux kernel guys about GCC's code generation oddities."

You don't even have to go as far as kernel developers. From a 'write once, compile everywhere' perspective, GCC is actually pretty bad. I used to work at a company that built and deployed to somewhere in the neighborhood of 20 different *nix platforms, over 6 different hardware architectures, running various GCC versions. Working around version- or backend-specific GCC issues was almost a daily task, and it wasn't getting any better with later versions.

It's not that GCC is 'bad', but it's not holy either, not by any stretch of imagination. There's a reason Apple decided to push clang as an alternative. I believe clang+LLVM will some day replace GCC on Linux and other platforms that use GCC as well.

No no, LLVM-GCC really isn't "real gcc".

All the backends which gcc publish share huge amounts of code, in particular all the optimizations framework in the shape of the SSA representation and GIMPLE, support for generating debugging information via DRAWF.

LLVM-GCC just takes the minimum amount of GCC and replaces the entire back-end.

I'll install Apple's LLVM frontend when I can use it to generate ppc object code.

LLVM has had a PowerPC backend for years http://llvm.org/docs/CodeGenerator.html#targetfeatures .

Do you mean something more specific?

Yes, I'm aware. It's Apple's LLVM that lacks PowerPC code generation:

http://stackoverflow.com/questions/7137480/how-do-i-add-ppc-...

http://www.cocoabuilder.com/archive/xcode/299924-no-ppc-from...

New tools lose support for obsolete platforms, film at 11?

It's been 6 years. The world has moved on, and Apple no longer has any commercial interest in PowerPC. You really expect them to keep bothering with it?

I'm not really concerned with Apple's financial interests. I'm concerned with their software tools and their demonstrated willingness to support the hardware they sell.

Show me a mass-market PC manufacturer that continues supporting 6 year old consumer hardware.

Nope, don't try to shift the issue. We're talking about simply allowing others to compile code for PPC — not releasing brand new operating systems. Apple isn't merely ignoring it — they're going out of their way to prevent even third-parties from supporting it.

I don't understand this belief that Apple should support obsolete technology.

Lion is the _second_ version of OS X not to even run on PPC. Why should the developer tools they distribute for Lion support it at all?

They're not "going out of their way to prevent third parties from supporting it" any more than everybody else who doesn't ship an operating system with a PPC compiler. That includes Windows, most Linux distros, your grandma, the corner grocer, President Obama…

Apple isn't actually stopping you from compiling for PPC. They just aren't shipping the compiler themselves. AFAIK, they don't ship any compilers for hardware they don't support — no VAX, no MIPS, no M68k — PPC is not special in that respect. I don't see what's so terrible about that.

I just downloaded Xcode Tools 1.0 from Apple's developer site, for free (I'm not a paid developer). Xcode 1.0 was released in 2003 for OS X 10.3.

Also available are 1.5, 2.3, 2.4, 2.4.1, 3.0, 3.1, 3.1.1, on through to the latest 4.x versions, free for the taking. All versions prior to 4 will happily build code for PowerPC.

What is it you think they're preventing anyone from doing again?

That's great. Now install one of those on Lion. And you can't run anything earlier than Lion on any Mac sold today.

If you are compiling for PPC architectures, why are Snow Leopard/Lion of any concern? This is just a pointless whine about nothing in particular. If we all shared your attitude to the advancement of technology, we'd all still be using punch cards. The PowerPC platform is dead. They announced it's death at least 7 years ago. Move on.

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