Vscode-cpptools: Clang Format option no longer works with recent version of clang-format

[jyavenard]

If "C_Cpp.clang_format_path" is set to null, or to an old 5.0 version of clang-format, Command-K Command-F works as expected, and everything is formatted as it should be.

However, more recent version of clang-format (first noticed with version clang-format version 5.0.0 (trunk) (llvm/trunk 295482))
Then Command-K Command-F does nothing.

I'm assuming it's a version issue...

[bobbrow]

Usually when formatting does nothing it's because:

1. clang-format is emitting an error (which we don't show you) or
2. the extension is blocked by an IntelliSense operation that never returns (another issue we need to fix).

I think the first item is the most prevalent and I have a code change which will output the error so you can address whatever the problem might be. But I haven't fully tested it yet so I'm not sure if it will make it into the March release or not at this point.

[jyavenard]

Would you have a suggestion to test what arguments are passed to clang-format so that I can better test and report the problem?

[feluxe]

I have the same problem.

[mgr-inz-rafal]

The same here with

clang-format version 6.0.0-svn326550-1~exp1~20180305180131.61 (branches/release_60)

Formatting doesn't work, there's no error message or any other feedback.

[danbrun]

I am also unable to use document formatting with the extension when C_Cpp.clang_format_path is null. I could not find any errors logged anywhere when running Format Document.

The issue appears to be with the included clang-format.exe file on Windows, at least from what I can tell. I tried running it directly from C:\Users\{user}\.vscode\extensions\ms-vscode.cpptools-0.15.0\LLVM\bin, but got the following errors:

• The code execution cannot proceed because VCRUNTIME140.dll was not found. Reinstalling the program may fix this problem.
• The code execution cannot proceed because MSVCP140.dll was not found. Reinstalling the program may fix this problem.

I tried copying MSVCP140.dll and VCRUNTIME140.dll from C:\Windows\System32 into the same directory as clang-format.exe but it resulted in this error instead: The application was unable to start correctly (0xc000007b). Click OK to close the application.

I am able to get code formatting to work by installing LLVM separately and setting C_Cpp.clang_format_path to the external install's location. It's much easier to set up the extension when the included clang format worked though, so hopefully this can be fixed!

[sean-mcmanus]

@danbsite The executable is the same as is shipped from http://releases.llvm.org/5.0.0/LLVM-5.0.0-win32.exe , although we do a Microsoft signing which alters the binary slightly. I've double checked and the binary appears to be the correct 32-bit binary so I don't know why you'd be having a problem unless your 32-bit Windows installation is corrupt. The clang-format we ship is 32-bit, so you should be copying the files from SysWOW64 and not System32, assuming your OS is 64-bit.

[danbrun]

@sean-mcmanus I just did a fresh install of Windows when I encountered this issue, but I will try again. Thank you for the information!

[danbrun]

I was able to fix the issue for myself by installing the x86 version of this: https://www.microsoft.com/en-us/download/details.aspx?id=53587

I had tried this earlier but used the wrong installer so it didn't work, as I didn't realize the included clang-format.exe was 32 bit. Thank you again @sean-mcmanus!

I find it strange that I needed to install this manually as I previously did not need to, but maybe in my old Windows setup I just already had a version installed from another program.

[mgr-inz-rafal]

I'm glad that you was able to fix it.

On Ubuntu though it still silently fails without any error message.

[sean-mcmanus]

@mgr-inz-rafal Do you have the 0.16.0-insiders released March 9th? The March 8th version didn't have the additional error messages: https://github.com/Microsoft/vscode-cpptools/releases/tag/v0.16.0-insiders .

[mgr-inz-rafal]

@sean-mcmanus No, I currently have Version 0.15.0: February 15, 2018 installed.
Will get back to you after an update.

[davydden]

I also don't have clang-format working without any error message, this is on macOS:

$ clang-format -version
clang-format version 6.0.0 (tags/RELEASE_600/final)

VSCode Version 1.21.1 (1.21.1), macOS 13.3.3.

I have both C_Cpp.clang_format_style and C_Cpp.clang_format_path set.

[sean-mcmanus]

@davydden We're planning to release 0.16.0 today, which should show the errors that clang-format is generating (you could also try the 0.16.0-insiders.

[davydden]

@sean-mcmanus

We're planning to release 0.16.0 today, which should show the errors that clang-format is generating (you could also try the 0.16.0-insiders.

thanks for the prompt reply, I will wait for the release and post back here tomorrow or so...

p.s. I indeed have 0.15.0 installed, forgot to mention this in the post above.

[davydden]

@sean-mcmanus i tried 0.16.0, Format selection indeed showed something like

Format failed, see output window for details

but output window was clean.

Subsequent calls produces neither errors nor output logs.

[davydden]

@sean-mcmanus

nevermind, I found logs in GUI (output tab and then C/C++), was not aware of this.

So the error is

Formatting failed:
/Users/<path-to>/clang-format -style=/users/<path-to>/.clang-format -fallback-style=LLVM -assume-filename=<path-to>/file.cc
  Invalid value for -style

whereas C_Cpp.clang_format_style starts with the capital U:

"C_Cpp.clang_format_style":"/Users/..."

so perhaps that's the reason.

[sean-mcmanus]

@davydden We don't accept style being a path. I don't think that's valid, right? Did clang-format 6.0 change to allow this? We do a lowercase operation on the style unless it starts with a {. We could change this to check for other conditions if they are valid. I've only seen .clang-format files being retrieved from the file system (current directory or parent) using the "file" option.

UPDATE: Yeah, your input to style appears to be incorrect according to http://clang.llvm.org/docs/ClangFormat.html (unless they haven't updated the docs yet to reflect this new input option).

[davydden]

@sean-mcmanus frankly, I am not sure how to interpret what clang 7.0 says

clang-format supports two ways to provide custom style options: directly specify style configuration in the -style= command line option or use -style=file and put style configuration in the .clang-format or _clang-format file in the project directory.

When using -style=file, clang-format for each input file will try to find the .clang-format file located in the closest parent directory of the input file. When the standard input is used, the search is started from the current directory.

I would say file is a path to .clang_format.

[davydden]

ah, it's not a path, it's really just a key... damn. Ok, i guess i was just using this wrong...

that's what help says:

-style= - Coding style, currently supports:
LLVM, Google, Chromium, Mozilla, WebKit.
Use -style=file to load style configuration from
.clang-format file located in one of the parent
directories of the source file (or current
directory for stdin).
Use -style="{key: value, ...}" to set specific
parameters, e.g.:
-style="{BasedOnStyle: llvm, IndentWidth: 8}"

EDIT: it worked perfectly fine by picking up .clang-format from the project root. Sorry the noise!

[sean-mcmanus]

Yeah, I understand how the docs could lead to that confusion -- I remember at least one other user hitting this issue as well. We could add it to our backlog to check for this type of error and warn or correct it.

[bobbrow]

Thanks for confirming. For the rest of the users on this issue, can you please try out 0.16.0 and look at the "C/C++" log channel of the Output window when your formatting fails? If you are unable to resolve your clang-format issues with the logging message, please open a new issue and we can help you resolve it.

I am going to close this issue now.

[mgr-inz-rafal]

Hi!
I see the issue is closed, but I promised you feedback, so here it is.

After updating extension to 0.16.1 I can see debug info in the console:

Formatting failed:
/usr/bin -style={ BasedOnStyle: LLVM, UseTab: Never, IndentWidth: 4, TabWidth: 4, BreakBeforeBraces: Allman, AllowShortIfStatementsOnASingleLine: false, IndentCaseLabels: false, ColumnLimit: 0 } -fallback-style=LLVM -sort-includes=0 -assume-filename=/home/rafal/tmp/test.cc

That clearly indicates problem with my "C_Cpp.clang_format_path" config, which is now solved.

Thanks!
Formatting works perfectly.