I am creating a unit test project using TinyEmbeddedTest. The main project in my solution builds and runs fine, but I am getting some linker errors on the unit test project.

The unit tests are in a source file called ADC.cpp, in the unit test project.  This file tests code in a file named ADC.c (which is in my main project) and so has the line:

#include “ADC.c”

The file ADC.c contains the following include lines:

#include “ADC.h”
#include “fault.h”

The errors are thrown in ADC.c, on the following statements:

if (status == SUCCESS)
{
Fault_Clear(FAULT_ADC_FAILURE);
rawADCValue = HAL_ADC_GetValue(hADC);
}
else
{
Fault_Set(FAULT_ADC_FAILURE);
rawADCValue = 0u;
}

The errors are:

undefined reference to ‘Fault_Clear’

undefined reference to ‘Fault_Set’

From this I can see that the header file, fault.h, where these functions are declared, is accessible to the toolchain, because otherwise there would be a compilation error, but the source file. fault.c, where these functions are defined, does not seem to be accessible.

I do not get these errors when running my main project, only in the unit test project.

I thought that perhaps the answer might lie in the project linker settings, and so I added a line to the Linker->[Additional Inputs] as follows:

C:\Development\myProject\VisualGDB\Debug\Src

I assumed that this would give the linker access to the .o files, created by the compiler. Unfortunately this created a new problem. The build now fails without any error messages. The list of build messages simply says

Build failed: arm-none-eabi-g++.exe exited with code 1

Id returned 1 exit status

and when I look at the log, it says

c:/sysgcc/arm-eabi/bin/../lib/gcc/arm-none-eabi/9.3.1/../../../../arm-none-eabi/bin/ld.exe: cannot find C:/Development/myProject/VisualGDB/Debug/Src: Permission denied

Interestingly, that last path is a hyperlink, and when I click on it, I get an error dialog box

Failed to open ‘C:\SysGCC\arm-eabi\Development\myProject\VisualGDB\Debug\Src’

This is especially odd, because I know that path does not exist, and that is definitely not the path that I entered in the Linker settings.

Any guidance would be much appreciated.