Pre-compiled libraries in the sketch folder

[davidpruitt]

Hey all,

I very often place my libraries as sub-folders in my sketch folder rather than using the typical Arduino library folder. So, for example, I may have a folder structure like this:

.\MySketch.ino
.\src\Adafruit_BME680\Adafruit_BME680.h
.\src\Adafruit_BME680\Adafruit_BME680.cpp

I do it this way for multiple reasons.

1. I have found that each project I work on has different requirements, and so often times I may need to "tweak" the code of a library for a certain project. I like to keep those "tweaks" private to a specific project rather than having those code changes explode and affect other projects I am working on.

2. I prefer to have all my code and all my dependencies fit into a single Github repository. In that way, I can easily just clone the repository and build. No need to install libraries on each and every development computer - because they are already in the repository as sub-folders of the sketch.

Anyway, I have recently been trying to use a library that includes a pre-compiled ".a" file, and I need to figure out how to get the ".a" file to link properly. The structure of the project is something like this:

.\MySketch.ino
.\src\my_precompiled_file.a

How can I get this file linked properly so I can use it?

If it matters: I am using a custom board definition, but it's pretty much the same as the Adafruit Grand Central M4 Express with a SAMD51 microcontroller (ARM Cortex M4).

Thanks!

[UKHeliBob]

Your topic was MOVED to its current forum category which is more appropriate than the original as it has nothing to do with Installation and Troubleshooting of the IDE

[johnwasser]

You can specify that the compiled library be kept and reused in the library.properties file. If you put a .a file in the expected place it will use that instead of re-compiling the library sources.

Start reading this post at reply 14:

Attempting to create small test precompiled sketch

I'm fairly new to Arduino and I've created an app for the Nano series with RS-232/LED connections. I'm using a small test program to learn the in's and out's of creating the library. I was able to create a library using the .h/.cpp listed below but when I try to make it a precompiled library, I'm failing to resolve in the link phase. I've read, probably 20+ posts that describe how to build by changing the library.properties with the dot_a_linkage and then changing to the precompile=true plus…

[davidpruitt]

Sorry, maybe I did not explain my situation well-enough in my previous post. I am trying to do something quite different than what you described in your answer.

Most people who use Arduino have a library folder, as you know, and all their sketches just simply include libraries from that library folder. While that is useful in many situations, I have found that in my personal situation I like to have each of my sketches have its libraries private to itself. Therefore, rather than keep them in a pre-defined library folder, I place code in sub-directories to the sketch.

So my situation is not like this:

If it were like that, then there would be a library.properties file, and I would make sure it had all the settings properly set as you suggested from that other thread. But my situation isn't like that.

I have a simple ".a" file sitting a sub-directory of my sketch. That's it. It's not off in some library somewhere else. I want to make sure that the pre-compiled ".a" file in my subdirectory of my sketch can get linked into my binary, and right now I am just getting compile-time errors attempting to do this. Any suggestions?