avr-gcc -mmcu command is omitted. -MF arg should be stripped

[patrykbajos]

Type: LanguageService

Describe the bug

• OS and Version: Linux x64 4.14
• VS Code Version: 1.31.1
• C/C++ Extension Version: 0.21.0
• Other extensions you installed (and if the issue persists after disabling them): vector-of-bool.cmake-tools, cheshirekow.cmake-format, platformio.platformio-ide
• A clear and concise description of what the bug is.

Processor specific command -mmcu=atmegaXX is not recognized properly.
https://www.microchip.com/webdoc/AVRLibcReferenceManual/using_tools_1using_avr_gcc_mach_opt.html
None of these macros are not present in IntelliSense.

To Reproduce

1. Make compile_commands.json for example:

[
    {
        "arguments": {
            "/usr/bin/avr-gcc",
            "-mmcu=atmega16",
            "-DF_CPU=1000000",
            "-c",
            "-o",
            ".../build/main.o",
            ".../src/main.c",
         },
        "directory": ".../src",
        "file": ".../src/main.c"
    }
]

2. Add it to your configuration compileCommands.
3. Try to check IntelliSense in any of files contined in your compileCommands..
4. F_CPU macro is recognized, hardware specific macros are not.

Expected behavior

I expect to have hardware specific defines such as __AVR_ATmega16__.
I expect to have properly recognized avr/io.h header. It is not because lack of define __AVR_ATmega16__.

Screenshots

Additional context

[sean-mcmanus]

This appears to be the same issue as #1755 .The current workaround is to set your compilerPath to "/usr/bin/avr-gcc -mmcu=...". Does that work for you? Or does it appear that our attempt to query the /usr/bin/avr-gcc is failing?

[patrykbajos]

I have tried /usr/bin/avr-gcc -mmcu=... (before posting Issue) as compilerPath. It was not working.

{
            "name": "Linux",
            "includePath": [
                "${workspaceFolder}",
                "${currentIncludes}"
            ],
            "defines": [],
            "intelliSenseMode": "clang-x64",
            "browse": {
                "path": [
                    "${workspaceFolder}"
                ],
                "limitSymbolsToIncludedHeaders": true
            },
            "compilerPath": "/usr/bin/avr-gcc -mmcu=atmega16",
            "cStandard": "c11",
            "cppStandard": "c++17",
            "compileCommands": "/home/patryk/Projects/ModularOS/compile-commands.json"
        }

Here is my configuration I am using. Compile command for file that I am testing is:

{
        "arguments": [
            "/usr/bin/avr-gcc",
            "-DNDEBUG",
            "-Os",
            "-I/home/patryk/Projects/ModularOS/modularos-core",
            "-I/home/patryk/Projects/ModularOS/modularos-usart",
            "-mmcu=atmega16",
            "-DF_CPU=16000000",
            "-c",
            "-o",
            "/home/patryk/Projects/ModularOS/build/release/obj_modularos-core_atmega16_16000000/modularos-core/system.o",
            "/home/patryk/Projects/ModularOS/modularos-core/modularos-core/system.c"
        ],
        "file": "/home/patryk/Projects/ModularOS/modularos-core/modularos-core/system.c",
        "directory": "/home/patryk/Projects/ModularOS"
    },

There are only defines like __AVR__ which are not specific to -mmcu=....

[bobbrow]

Did you try with the 0.22.0-insiders build? There was a bug in the current release version of the extension where compilerPath did not override the compiler in compile_commands.json.

[patrykbajos]

Bob Brown (@bobbrow) I have tested 0.22.0-insiders and defines are working as it should. -mmcu= in compile_commands.json is still not working but it works with use of compilerPath.

[bobbrow]

This may be fixed with 0.29.0 (which is not released yet). We added support for more args in compile_commands.json.

[sean-mcmanus]

Is this fixed with 0.29.0?

[MrMartin92]

For me it is still not working.

Here is a sample source file I created for testing. You can see the section with __AVR_DEVICE_NAME__ is not active and therefore all symbols like DDRD are missing. On the other hand __AVR__ is working fine. You can see I have installed version 0.29.0 on the left side.

Here is my compiler_commands.json which I generate with compiledb and make.

A quick look with avr-gcc -dM -E -mmcu=atmega328p shows that __AVR_DEVICE_NAME__ gets clearly defined.

So -mmcu=atmega328p gets still ignored.