[llvm-dev] Switching to Ninja

[David Blaikie via llvm-dev]

On Sun, Aug 9, 2020 at 8:03 AM Paul C. Anagnostopoulos
<paul at windfall.com> wrote:
>
> You are correct, sir. Everything works much better if I run CMake and Ninja from a "developer command prompt." I displayed the path and almost fell off my chair laughing. The road to hell is paved with environment variable entries.
>
> Two questions.
>
> 1. Building with Visual Studio created build/release/bin. Building with Ninja created build/bin (no release directory). Does that make sense? (I have -DCMAKE_BUILD_TYPE=Release on the cmake command.)

sounds plausible to me that different build systems may require or
prefer different layouts - though I have no specific knowledge

> 2. The first build attempt failed because the existing TableGen Language Reference has multiple instances of the production 'SimpleValue', which produces warnings from Sphinx. I fixed that by adding -DSPHINX_WARNINGS_AS_ERRORS:BOOL=OFF to the cmake command. Does the official build do that, too? I searched all the CMakeLists files but didn't find any use of that option.

Not sure. I guess some buildbots probably build with it on/I've
certainly seen some folks commit follow-up/cleanup patches to try to
keep the Sphinx warning-clean.

>
>
> At 8/8/2020 09:48 PM, David Blaikie wrote:
> >On Sat, Aug 8, 2020 at 5:27 PM Paul C. Anagnostopoulos
> ><paul at windfall.com> wrote:
> >>
> >> Sigh. I ask for your indulgence yet again.
> >>
> >> I installed Ninja and deleted my old build tree. When I run CMake now, I'm told that it can't find the compilers and assembler. So, of course, I need to put a compiler toolset on my path. I tried MinGW but was instantly reminded that it doesn't have localtime_s. So I tried to find the Visual Studio binaries and located four different directories. I added what I thought was the correct one to my path. CMake found the compiler, but it failed to compile CMake's test.
> >
> >I /think/ you're probably best using a Visual Studio shell - I /think/
> >you want to use a command prompt like this:
> >https://docs.microsoft.com/en-us/dotnet/framework/tools/developer-command-prompt-for-vs
> >that sets up everything right in the PATH.
> >
> >>
> >> Is anyone running Ninja with Visual Studio who might have a suggestion? I can't find anything in "Building LLVM with CMake."  I've attached the CMake output below.
>