Correct check for the ARM toolchain binary in the PATH.

[bridadan]

Description

Fixes #10039

The compiler used for the ARM toolchain changes depending on the target.
This changes the front end scripts to do the proper toolchain look up
before checking the system PATH for the compiler executable. The tools
were always checking for the ARMC5 compiler, now it should check for the
right version.

FYI @SenRamakri

Pull request type

[x] Fix
[ ] Refactor
[ ] Target update
[ ] Functionality change
[ ] Docs update
[ ] Test update
[ ] Breaking change

Reviewers

Release Notes

[ciarmcom]

@bridadan, thank you for your changes.
@ARMmbed/mbed-os-tools @ARMmbed/mbed-os-maintainers please review.

[theotherjimmy]

Looks fine.

[SenRamakri]

@ChiefBureaucraticOfficer - Can we make this change go in for 5.12.rc3? Currently this is marked for 5.12.1.
This actually fixes the issue where the ARMC6 compilation fails without proper message when ARMC6 is not available/configured.

Tagging @ARMmbed/mbed-os-maintainers @0xc0170 @cmonr @screamerbg

[bridadan]

What we currently print:

mbed compile -t ARM -m UBLOX_C030_U201
[mbed] WARNING: If you're using Python 3 with Mbed OS 5.8 and earlier versions, Python errors will occur when compiling, testing and exporting
---
[mbed] Working path "C:\Users\bridan01\onedrive_arm\Documents\dev\mbed-os" (program)
[OS ERROR] Command: armclang --vsn
[ERROR] [WinError 2] The system cannot find the file specified
[mbed] ERROR: "C:\Users\bridan01\AppData\Local\Programs\Python\Python36-32\python.exe" returned error.
       Code: 1
       Path: "C:\Users\bridan01\onedrive_arm\Documents\dev\mbed-os"
       Command: "C:\Users\bridan01\AppData\Local\Programs\Python\Python36-32\python.exe -u C:\Users\bridan01\onedrive_arm\Documents\dev\mbed-os\tools\make.py -t ARM -m UBLOX_C030_U201 --source . --build .\BUILD\UBLOX_C030_U201\ARM"
       Tip: You could retry the last command with "-v" flag for verbose output
---
[mbed] WARNING: Using Python 3 with Mbed OS 5.8 and earlier can cause errors with compiling, testing and exporting
---

What will be printed after this change:

mbed compile -t ARM -m UBLOX_C030_U201
[mbed] WARNING: If you're using Python 3 with Mbed OS 5.8 and earlier versions, Python errors will occur when compiling, testing and exporting
---
[mbed] Working path "C:\Users\bridan01\onedrive_arm\Documents\dev\mbed-os" (program)
usage: make.py [-h] [-m MCU] [--custom-targets CUSTOM_TARGETS_DIRECTORY]
               [-t TOOLCHAIN] [--color] [--cflags CFLAGS]
               [--asmflags ASMFLAGS] [--ldflags LDFLAGS] [-c]
               [--profile PROFILE] [--app-config APP_CONFIG]
               [-p PROGRAM | -n PROGRAM | -L | -S [{matrix,toolchains,targets}]]
               [-j JOBS] [-v] [--silent] [-D MACROS] [-f GENERAL_FILTER_REGEX]
               [--stats-depth STATS_DEPTH] [--automated] [--host HOST_TEST]
               [--extra EXTRA] [--peripherals PERIPHERALS]
               [--dep DEPENDENCIES] [--source SOURCE_DIR]
               [--duration DURATION] [--build BUILD_DIR] [-N ARTIFACT_NAME]
               [--ignore IGNORE] [-b BAUD] [--rpc] [--usb] [--dsp] [--testlib]
               [--build-data BUILD_DATA] [-l LINKER_SCRIPT]
make.py: error: Could not find executable for ARMC6.
Currently set search path: No path set
[mbed] ERROR: "C:\Users\bridan01\AppData\Local\Programs\Python\Python36-32\python.exe" returned error.
       Code: 2
       Path: "C:\Users\bridan01\onedrive_arm\Documents\dev\mbed-os"
       Command: "C:\Users\bridan01\AppData\Local\Programs\Python\Python36-32\python.exe -u C:\Users\bridan01\onedrive_arm\Documents\dev\mbed-os\tools\make.py -t ARM -m UBLOX_C030_U201 --source . --build .\BUILD\UBLOX_C030_U201\ARM"
       Tip: You could retry the last command with "-v" flag for verbose output
---
[mbed] WARNING: Using Python 3 with Mbed OS 5.8 and earlier can cause errors with compiling, testing and exporting
---

This is consistent with our other toolchains if the path to the compiler executable is not properly configured (or found in the system PATH).

[cmonr]

CI started

[screamerbg]

@bridadan It's confusing that when armcc is not found, I get help from make.py. with different command options than mbed complie.

[theotherjimmy]

@screamerbg I think that's out of scope for this PR. Do we have an issue for that in this issue tracker?

[bridadan]

@screamerbg I agree with you, I've created an issue here to track it: #10090

The fix should be pretty small, just need to double check how it affects the other front-end scripts (build.py, make.py, etc)

[mbed-ci]

Test run: FAILED

Summary: 1 of 13 test jobs failed
Build number : 1
Build artifacts

Failed test jobs:

• jenkins-ci/mbed-os-ci_exporter

[cmonr]

Going to restart the exporter job again.

We might be having license issues with ARMc6.

[0xc0170]

@SenRamakri Thanks for the info!