It is, though. And Microsoft isn't alone in hating GNU - FreeBSD no longer ships with or uses GCC; the entire FreeBSD kernel and userland is built with Clang these days. And, of course, Apple's the one that started this whole stampede away from GCC in the first place. LLVM/Clang really and truly have hit GCC hard - and definitely for the best. Look at the improvements to GCC spurred by newer features in the Clang build toolchain.
EDIT:
In reply to davidgerard's comment below:
> I will not believe this falsifiable claim without numbers. FreeBSD has almost no users compared to Linux.
Non-Windows does not mean Linux.
And what falsifiable claim? They didn't say Clang is the most popular - they said it's becoming. But if that's really the game you want to play, then it's Linux that has almost no users compared to the number of iPhones/iPads/iWatches/MacBooks out there - Clang/LLVM-powered, each and every one of them.
Another contributing factor may be momentum. Clang is easier to work with than GCC, and doesn't have the baggage of GCC, so more and more people and companies are starting to use it, fund it, and commit code to it. It's been improving in leaps and bounds, and still rapidly improving. It's only a matter of time before it's all around better than GCC.
> I am wondering what are the technical reasons though
This is based on fairly limited experience, but I believe it's simply a better toolset. LLDB was easier to work with for me. The error messages make things quicker to diagnose. I prefer the added verbosity for things like flags.
GP actually used falsifiable properly - meaning that the claim is testable (evidence could swing both ways). A non-falsifiable claim would just have to be taken on faith alone or rejected altogether
Define "user". You're on the internet. The bits you're downloading are probably passing through devices somewhere in the path that run FreeBSD.
~30% of North American traffic is from Netflix, whose servers are FreeBSD.
Everyone is a FreeBSD user and they don't need to know it to for it to count. Nobody actually gives a shit about numbers of users sitting on FreeBSD desktops.
That's not correct. Apple needed technical things from a compiler that gcc could not feasibly do, and started moving things to LLVM before GPLv3 was released. Even if gcc had been relicensed under a permissive license such as BSD, Apple would have moved to LLVM and Clang.
A couple examples. Core Image needs an optimizing JIT compiler that can take a chain of image filters and turn it into a single efficient filter for execution on the GPU or CPU (whichever will be faster on the particular system for the particular effects). XCode needs to parse C/C++/Objective-C code in the editor and in the debugger.
What Apple needed for these things was a modular compiler system, designed to work as a compiler toolkit from which you can pick and choose the parts that you need for your particular needs. A compiler toolkit that is designed to be easy to interface with outside tools.
Gcc was explicitly designed to not be that. It was only competition from LLVM/Clang that forced some liberalization onto gcc.
EDIT:
In reply to davidgerard's comment below:
> I will not believe this falsifiable claim without numbers. FreeBSD has almost no users compared to Linux.
Non-Windows does not mean Linux.
And what falsifiable claim? They didn't say Clang is the most popular - they said it's becoming. But if that's really the game you want to play, then it's Linux that has almost no users compared to the number of iPhones/iPads/iWatches/MacBooks out there - Clang/LLVM-powered, each and every one of them.