Identical compiler warnings in problems panel

[Lightirius]

Brief Issue Summary

When compiling a project with multiple translation units that have warnings in some common include file they are shown multiple times. All of them work and open the same file in the same position.

Expected:

There are no identical warnings.

Apparent Behavior:

Identical warnings are shown.

Minimal project to reproduce:
CmakeLists.txt:

cmake_minimum_required(VERSION 3.16)
project(Test)

add_executable(Test main.cpp Foo.cpp)
target_compile_options(Test PRIVATE -Wextra)

main.cpp:

#include "Foo.hpp"
#include "Duplicate.hpp"

int main() { return 0; }

Foo.hpp:

#pragma once

#include "Duplicate.hpp"

Foo.cpp:

#include "Foo.hpp"

Duplicate.hpp:

#pragma once

class Duplicate {
public:
  void test(int i) {}
};

Multiple unused-parameter warnings should be shown in problems pannel.

Build output:

[main] Building folder: Test clean
[build] Starting build
[proc] Executing command: /usr/bin/cmake --build /mnt/media/dev/projects/Test/build/Clang-linux/Debug --config Debug --target clean --
[build] [1/1 100% :: 0.003] Cleaning all built files...
[build] Cleaning... 3 files.
[build] Build finished with exit code 0
[main] Building folder: Test 
[build] Starting build
[proc] Executing command: /usr/bin/cmake --build /mnt/media/dev/projects/Test/build/Clang-linux/Debug --config Debug --target all -- -j 18
[build] [2/3  33% :: 0.022] Building CXX object CMakeFiles/Test.dir/Foo.cpp.o
[build] In file included from ../../../Foo.cpp:1:
[build] In file included from ../../../Foo.hpp:3:
[build] ../../../Duplicate.hpp:5:17: warning: unused parameter 'i' [-Wunused-parameter]
[build]   void test(int i) {}
[build]                 ^
[build] 1 warning generated.
[build] [2/3  66% :: 0.022] Building CXX object CMakeFiles/Test.dir/main.cpp.o
[build] In file included from ../../../main.cpp:1:
[build] In file included from ../../../Foo.hpp:3:
[build] ../../../Duplicate.hpp:5:17: warning: unused parameter 'i' [-Wunused-parameter]
[build]   void test(int i) {}
[build]                 ^
[build] 1 warning generated.
[build] [3/3 100% :: 0.330] Linking CXX executable Test
[build] Build finished with exit code 0

Platform and Versions

• Operating System: Arch Linux
• CMake Version: 3.17.3
• VSCode Version: Latest insiders
• CMake Tools Extension Version: 1.4.1
• Compiler/Toolchain: Clang 10.0.0

Other Notes/Information

[github-actions]

This issue is now marked as 'stale-old' due to there being no activity on it for the past 720 days. Unless the 'stale-old' label is removed or the issue is commented on, this will be remain open for at least 14 days and then it may be closed. If you would like to make this issue exempt from getting stale, please add the 'stale-exempt' label.

[Lightirius]

Still happening with cmake-tools 1.15.31

[gcampbell-msft]

Sean McManus (@sean-mcmanus) Bob Brown (@bobbrow) Should this be transferred to vscode-cpptools? Or is this actually a cmake-tools issue. Thanks!

[sean-mcmanus]

Garrett Campbell (@gcampbell-msft) It seems external to me. The warnings are coming from GCC. The user can set the command line arguments to disable the warnings or fix the warnings.

[sean-mcmanus]

Garrett Campbell (@gcampbell-msft) Oh, I see the bug is with the duplicates -- still, it's coming from the "GCC" problem matcher which isn't from our extension (our extension provides the "gcc" problem matcher, lower cased).

[gcampbell-msft]

Lightirius It seems like this issue may be coming from whatever is providing the "GCC" problem matcher, do you have an extension contributing this or some other problem matcher set up?

[Lightirius]

Garrett Campbell (@gcampbell-msft) Retested with only cmake-tools installed - this is the build output from the same minimal project:

"cmake-build-diags" matcher is not from cmake-tools extension?

Also it's not exactly a bug, more of a feature request to filter identtical warnings/errors from build output

Full output from configure+build:

[main] Building folder: cmake-tools-duplicated-warnings clean
[proc] Executing command: D:\apps\scoop\shims\cmake.EXE --version
[proc] Executing command: D:\apps\scoop\shims\cmake.EXE -E capabilities
[main] Configuring project: cmake-tools-duplicated-warnings 
[proc] Executing command: D:\apps\scoop\shims\cmake.EXE -DCMAKE_BUILD_TYPE=Debug -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_CXX_STANDARD=20 -DCMAKE_CXX_STANDARD_REQUIRED=YES -DCMAKE_CXX_EXTENSIONS=OFF -DCMAKE_EXPORT_COMPILE_COMMANDS=YES -DCMAKE_INSTALL_PREFIX=S:/dev/projects/bugs/cmake-tools-duplicated-warnings/out/install/Clang-Debug -SS:/dev/projects/bugs/cmake-tools-duplicated-warnings -BS:/dev/projects/bugs/cmake-tools-duplicated-warnings/out/build/Clang-Debug -G Ninja
[cmake] -- Configuring done (0.1s)
[cmake] -- Generating done (0.0s)
[cmake] -- Build files have been written to: S:/dev/projects/bugs/cmake-tools-duplicated-warnings/out/build/Clang-Debug
[build] Starting build
[proc] Executing command: chcp
[proc] Executing command: D:\apps\scoop\shims\cmake.EXE --build S:/dev/projects/bugs/cmake-tools-duplicated-warnings/out/build/Clang-Debug --parallel 18 --target clean
[build] [1/1] Cleaning all built files...
[build] Cleaning... 3 files.
[driver] Build completed: 00:00:00.152
[build] Build finished with exit code 0
[main] Building folder: cmake-tools-duplicated-warnings 
[build] Starting build
[proc] Executing command: D:\apps\scoop\shims\cmake.EXE --build S:/dev/projects/bugs/cmake-tools-duplicated-warnings/out/build/Clang-Debug --parallel 18
[build] [1/3] Building CXX object CMakeFiles/Test.dir/main.cpp.obj
[build] In file included from S:/dev/projects/bugs/cmake-tools-duplicated-warnings/main.cpp:1:
[build] In file included from S:/dev/projects/bugs/cmake-tools-duplicated-warnings/Foo.hpp:3:
[build] S:/dev/projects/bugs/cmake-tools-duplicated-warnings/Duplicate.hpp:5:17: warning: unused parameter 'i' [-Wunused-parameter]
[build]     5 |   void test(int i) {}
[build]       |                 ^
[build] 1 warning generated.
[build] [2/3] Building CXX object CMakeFiles/Test.dir/Foo.cpp.obj
[build] In file included from S:/dev/projects/bugs/cmake-tools-duplicated-warnings/Foo.cpp:1:
[build] In file included from S:/dev/projects/bugs/cmake-tools-duplicated-warnings/Foo.hpp:3:
[build] S:/dev/projects/bugs/cmake-tools-duplicated-warnings/Duplicate.hpp:5:17: warning: unused parameter 'i' [-Wunused-parameter]
[build]     5 |   void test(int i) {}
[build]       |                 ^
[build] 1 warning generated.
[build] [3/3] Linking CXX executable Test.exe
[driver] Build completed: 00:00:00.953
[build] Build finished with exit code 0

CmakePresets.json used for configuration:

{
   "version": 2,
   "cmakeMinimumRequired": {
      "major": 3,
      "minor": 20,
      "patch": 0
   },
   "configurePresets": [
      {
         "name": "Base",
         "hidden": true,
         "binaryDir": "${sourceDir}/out/build/${presetName}",
         "generator": "Ninja",
         "cacheVariables": {
            "CMAKE_CXX_STANDARD": "20",
            "CMAKE_CXX_STANDARD_REQUIRED": "YES",
            "CMAKE_CXX_EXTENSIONS": "OFF",
            "CMAKE_EXPORT_COMPILE_COMMANDS": "YES",
            "CMAKE_INSTALL_PREFIX": "${sourceDir}/out/install/${presetName}"
         }
      },
      {
         "name": "Clang-Debug",
         "displayName": "Clang Debug",
         "inherits": "Base",
         "cacheVariables": {
            "CMAKE_BUILD_TYPE": "Debug",
            "CMAKE_C_COMPILER": "clang",
            "CMAKE_CXX_COMPILER": "clang++"
         }
      }
   ]
}

[sean-mcmanus]

Lightirius cmake-build-diags is from the cmake-tools extension, but I don't think that is fixable using problem matchers, and the identical compiler warnings are from building different 2 different translation units with the same header, so it's somewhat "by design".

[Lightirius]

Sean McManus (@sean-mcmanus), sorry for a long delay
If it's working as intended or not an issue with cmake-tools feel free to close this issue or change it to a feature request instead

Out of curiocity, i've checked how vs-code problem matchers in tasks handle this situation.
I may be missing something, but with this tasks.json file there are no duplicated messages in problems panel:

{
    // See https://go.microsoft.com/fwlink/?LinkId=733558
    // for the documentation about the tasks.json format
    "version": "2.0.0",
    "tasks": [
        {
            "label": "Custom Cmake build",
            "type": "shell",
            "command": "cmake --build .",
            "options": {
                "cwd": "${workspaceFolder}/out/build/Clang-Debug"
            },
            "problemMatcher": {
                "owner": "cpp",
                "fileLocation": "absolute",
                "pattern": {
                    "regexp": "^(.*):(\\d+):(\\d+):\\s+(warning|error):\\s+(.*)$",
                    "file": 1,
                    "line": 2,
                    "column": 3,
                    "severity": 4,
                    "message": 5
                }
            }
        }
    ]
}

I am not a TS dev and don't really know how VS code plugins work so the next part may be wrong/irrelevant.

I've dug a little bit into the cmake-tools implementation to find where diagnostics are parsed and collected.
It looks like they are parsed and initially collected in:

vscode-cmake-tools/src/diagnostics/util.ts

Line 101 in 15c6e4c

handleLine(line: string): boolean {

Then converted to VS Code diagnostics in:

vscode-cmake-tools/src/diagnostics/build.ts

Line 49 in 15c6e4c

resolveDiagnostics(basePath: string): FileDiagnostic[] {

And finally put into DiagnosticCollection in:

vscode-cmake-tools/src/diagnostics/util.ts

Line 68 in 15c6e4c

export function populateCollection(coll: vscode.DiagnosticCollection, fdiags: Iterable<FileDiagnostic>) {

For me, it looks like it should be relatively straightforward to implement some sort of filtering in one of those places

[sean-mcmanus]

Lightirius Yeah, it looks like you're right -- I mistakenly thought they implemented it with a problemMatcher in their package.json (like the gcc problem matcher in vscode-cpptools), but it is not.