ISO Updates C Standard

An anonymous reader writes "The International Organization for Standardization (ISO) has published the new specifications for the C programming language. The standard is known unofficially as C1X and was published officially as ISO/IEC 9899:2011. It provides greater compatibility with the C++ language and adds new features to C (as indicated in the draft)."

Let's get C99 right first

[JDG1980]

Currently, Microsoft Visual Studio does not even support the C99 standard. Unfortunately, it's unlikely that this standard will be widely adopted any time soon when Microsoft seems to be content to let standard C wither and die.

Re:First post!!

[Anonymous Coward]

Oh? $300? For a PDF file? Heh.

Re:Let's get C99 right first

[wdef]

C is withering and dying? Isn't it still used more than any other language: http://langpop.com/ [langpop.com]

Draft available for free

[FrangoAssado]

For those interested, the last draft before the official version is available for free here: http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf [open-std.org]

Re:So...

[Old Wolf]

http://en.wikipedia.org/wiki/C1X [wikipedia.org]

Re:Let's get C99 right first

[JDG1980]

Unfortunately, the damage goes beyond that. You can't effectively use GCC (MinGW) to build most Windows applications, not only because these applications are full of Visual C++isms, but also because many newer APIs (notably Direct2D and DirectWrite) are not currently supported under MinGW at all.

Re:Let's get C99 right first

[Anonymous Coward]

"This includes even the most basic stuff, like declaring variables in the middle of your code. It's actually a GCC extension to C"

No it's not— it's part of ISO C99.

Looks like story is already dated...

[ibsteve2u]

The standard is known unofficially as C1X

GCC already says: [gnu.org]

A fourth version of the C standard, known as C11, was published in 2011 as ISO/IEC 9899:2011. GCC has limited incomplete support for parts of this standard, enabled with -std=c11 or -std=iso9899:2011. (While in development, drafts of this standard version were referred to as C1X.)

Syntax is everything in C.

Poul-Henning's take on this.

[Anonymous Coward]

https://www.varnish-cache.org/docs/trunk/phk/thetoolsweworkwith.html

Re:Let's get C99 right first

[Anonymous Coward]

For a windows developer MS make their proprietary C# language easy, and C hard work. Now for most stuff that's fine, but sometimes a lower level language is needed.

Interesting, it's like you've never heard of C++ which MS does fully support [slowly] and is standard. I know pure C is a sacred cow but writing pure procedural code in C++ won't kill you, in fact, it will probably make the code much easier to read since you can't just arbitrarily cast back and forth between void pointers and other types without explicit type brackets.

Ever tried writing a kernel mode driver in C#?

MS has been experimenting with that but it seems more likely that they'll just hoist most drivers into user space services so you can use any language, .Net based or not. They've already hoisted some USB drivers and the bulk of WDDM video card drivers, just backwards compatibility in the way for the rest.

Re:Let's get C99 right first

[rev0lt]

Actually, C# is as proprietary as C - it isn't. Check http://msdn.microsoft.com/en-us/netframework/aa569283 [microsoft.com] for the ISO standard details regarding C#.
Microsoft .NET implementation is proprietary, but there is an early open source release of the .NET CLI implementation codenamed "Rotor", for XP, FreeBSD and MacOS X. Additionally, the Mono project is an opensource clean-room implementation, but it may not be feature-complete.

Microsoft Research has an interesting project called Singularity - an operating system running (mostly) in managed code. Some initialization routines are done in Assembly/C/C++, but the kernel itself and respective drivers are written entirely in managed code. Check http://en.wikipedia.org/wiki/Singularity_(operating_system) [wikipedia.org].

Re:First post!!

[TheRaven64]

The last draft and the errata are always free downloads. That's what I've been using to implement the atomics stuff in clang / FreeBSD.

Re:Let's get C99 right first

[TheRaven64]

GCC? People still use that? Clang can now parse a lot of the standard windows headers. 3.1 should have finished implementing the required quirks to understand the Windows templates. There's also work underway to support the Win64 exception model, which will hopefully be done by the 3.1 release.

Re:First post!!

[wzzzzrd]

It's 300 bucks, it was produced by a committee financed by tax payer's money, it's a pdf, not even a printed book. It's an open standard and will be needed by a lot of developers who want or must write standard compliant code. This is EXACTLY the thing RMS means when he is shouting his song.

Grab the original file from here [thepiratebay.org].

Re:So...

[TheRaven64]

As with every other version of the C standard, you can read the draft yourself [open-std.org]. A few things that are nice:

• A detailed and well-thought-out set of atomic operations. I've got a diff for clang that implements these that should be committed in the next few days after a bit of tidying. Ed Schouten has written the supporting header to FreeBSD libc, so these can be used now (with fall back to GCC intrinsics for a marginally slower implementation).
• Unicode string literals and a few functions for manipulating them.
• _Generic() letting you write type-generic macros.
• Anonymous structure and union members, so you can write things like struct { int tag; union { void *ptr; uintptr_t i}; } s; and then refer to s.ptr or s.i, rather than needing to provide a name for the union (this is already a GNU extension, but it's nice to have it in the standard).
• Static assertions, so you can do things like _Static_assert(sizeof(int) == 4, "This code path should not be used in ILP64 platforms!"); and get a compile-time error if it is.
• A _Thread_local storage qualifier for thread-local variables (equivalent to the __thread GNU extension).
• Alignment checks and specifiers.
• A few things from POSIX, like the x specifier in fopen() for exclusive open.

Some of the not-so-nice features include threads.h, which is equivalent to pthreads but with a different function names (and ones that seem quite likely to cause conflicts with existing code).

Re:Let's get C99 right first

[shutdown -p now]

Simply put, gcc beats VC on standard compliance, and VC beats gcc on optimization quality.

Anyway, VC is primarily a C++ compiler. C support is largely legacy, and hasn't been updated for a long time now.

Re:First post!!

[bonch]

This is EXACTLY the thing RMS means when he is shouting his song.

Of course, when he's not doing that, he's advocating necrophilia [stallman.org] and "voluntary pedophilia" [stallman.org]. Maybe not the best spokesperson to get behind.