On Thu, 3 Feb 2022, Kacper Michajlow wrote:

On Wed, 26 Jan 2022 at 15:00, Martin Storsjö <mar...@martin.st> wrote:

Hi,

On Sat, 22 Jan 2022, Kacper Michajłow wrote:

LLVM tools print installation path upon execution. If one uses LLVM
tools bundled with Microsoft Visual Studio installation, they would be
incorrectly detected as Microsoft's ones.

Signed-off-by: Kacper Michajłow <kaspe...@gmail.com>
---
configure | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

While the patch description seems to make sense, I wanted to try it out to
see the practical effect for myself, and I fail to observe any difference.

Can you provide your exact configure command line you use, where it makes
a difference? I tried with "--cc=clang-cl --ld=lld-link --toolchain=msvc"
and that works just as fine before this patch.

In particular, the commands that you adjust run "$_cc -nologo-" and grep
for "Microsoft" in the output of that. When I run that with clang-cl, it
doesn't print a string containing "Microsoft".

// Martin

Hi,

Yes you are right. In case of CC it doesn't change anything. clang-cl
prints installation dir only with `-v`. The main thing this patch
fixes is `--ar=llvm-ar` where it is mistaken for lib.exe and used with
wrong parameters. While fixing this I figured to make CC check also
more strict, because at some point it could be a problem. Sync all of
them to have same style as one that was already there

Oh, ok, with the reference to llvm-ar, I see what it fixes. Thanks! The reference to llvm-ar absolutely needs to be in the patch description then.

I remember that there has been some variance throughout the versions for exactly what MSVC prints as the identification thoughout the versions, but I think 'Microsoft.*Optimizing.*Compiler' should be safe.

So, the patch is ok if you equip it with a more detailed commit message.

Relatedly, I figured that it would be even more consistent to use --ar=llvm-lib instead of --ar=llvm-ar, when working in an MSVC style configuration, but we don't identify llvm-lib as the right kind of tool. Would you be interested in fixing that too? :-)

elif $_cc 2>&1 | grep -q 'Microsoft.*ARM.*Assembler'; then

just for consistency...

Also I noticed that latest MSVC (19.30.30709) complains about
cl : Command line warning D9035 : option 'nologo-' has been deprecated and will 
be removed in a future release

But it doesn't affect anything, even if it were to be removed. Since
banner is shown always by default, unless `-nologo`. Just a side note
:)

Yep - I think this has been an attempt to make sure it does get printed, even if someone passes e.g. "--cc='cl -nologo'". As long as it doesn't break, I guess it's no rush to change this.

// Martin
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