Library.json ignored build.unflags

Libraries
1

Hi all,

I’m building a platformio library that needs to remove some flags for the compilation process to run successfully.

Here’s the Build part inside library.json

"build" : {
        "unflags": ["-std=gnu++98", "-std=c++11"],
        "flags" : [
            "-std=gnu++14",
            "-D HSE_CLOCK=8000000 -D DEBUG_BUILD"
        ],
        "extraScript": "scripts/gen_configs.py"
    },

The compilation fails and if in the script I dump the scons evironment to check if it’s working and I can’t see the BUILD_UNFLAGS field.

If in the platformio.ini of the project that is using the library I add the following line everything is working perfectly:

build_unflags = -std=gnu++98 -std=c++11

is it a bug or am I doing it wrong?

2

It may be that the unflags only applies when building the source code of that specific library?

Otherwise, try upgrading your core version (cli + pio upgrade --dev) and retry. If it still doesn’t work, seek guidance at Issues · platformio/platformio-core · GitHub.

3

I tried with the upgrade and it didn’t work, so I opened an Issue.

I don’t get what you mean. The project should be compiling the library source code.

4

I meant there might be difference between the flags being applied when the sources in src/ are compiled vs the one in the library in lib/ etc.

5

Ah, ok. Checked. There is no difference.

1 Like
6

Hi all! I am having the same issue related before. I am working with a platformio library and I need to add and remove some flags. I have this in the library.json.

    "build": {
        "flags": [
            "-std=c++2a",
            "-std=gnu++2a"
        ],
        "unflags": [
            "-std=gnu++11"
        ]
    },

Despite this, when running pio run -v, I still see -std=gnu++11 being added to the compilation command.

Does anyone have insights on how to resolve this? Is it worth reopening the GitHub issue?

Thanks in advance for your help!

7

The compilation command for which file? One of the source files of the library or a totally different file?

8

I am using the library in another project adding it using the Platformio lib_deps attribute.
It happen when compiling this project that uses the library.

9

What’s that project’s platformio.ini?

10

Here is the platformio.ini:


[env:ttgo-t-beam]
platform = espressif32
board = ttgo-t-beam
framework = arduino
monitor_speed = 115200
lib_deps =
    https://github.com/LoRaMesher/LoRaMesher#new_loramesher