Use the Keil µVision compiler from the windows command line.

KeiluVisionBuilder.cmd

@echo off
setlocal
:: KeiluVisionBuilder.cmd
:: Written by Flemming Steffensen, 2019.
:: Free for use and abuse by anyone.
:: ======================
:: Configuration

set WaitForLicenseTimeout=60
set BuildAttemptsMax=10

set "ProjectFileName=bootloader.uvprojx"
set "ProjectPath=MyProject\bootloader\"
set "Compiler=C:\Keil_v5\UV4\UV4.exe"
set "OutFolder=out_585\"
:: ======================
:: Do not edit below this line
set BuildAttempt=0

pushd %ProjectPath%

:PerformBuild
echo:
echo:Performing Keil Build...

if exist build.log                   del build.log
if exist %OutFolder%*.build_log.htm  del %OutFolder%*.build_log.htm

start /wait %Compiler% -j0 -b %ProjectFileName% -o build.log
set ReportedError=%ERRORLEVEL%

:: Scan build.log to determine if the license is locked.
find /c "Error: *** All Flex licenses are in use! ***" build.log  >nul
if %errorlevel% equ 0 (
    set /a BuildAttempt=%BuildAttempt% + 1 
    echo:Error: *** All Flex licenses are in use!
    if %BuildAttempt% equ %BuildAttemptsMax% goto NoLicenseAvailable
    echo:Retrying ^(%BuildAttempt% of %BuildAttemptsMax%^) in %WaitForLicenseTimeout% seconds
    waitfor SignalNeverComming /T %WaitForLicenseTimeout% >nul 2>&1
    goto PerformBuild
) 
:: Scan alternative build.log to determine if the license is locked.
find /c "Failed to check out a license" %OutFolder%*.build_log.htm >nul
if %errorlevel% equ 0 (
    set /a BuildAttempt=%BuildAttempt% + 1 
    echo:Error: Failed to check out a license
    if %BuildAttempt% equ %BuildAttemptsMax% goto NoLicenseAvailable
    echo:Retrying ^(%BuildAttempt% of %BuildAttemptsMax%^) in %WaitForLicenseTimeout% seconds
    waitfor SignalNeverComming /T %WaitForLicenseTimeout% >nul 2>&1
    goto PerformBuild
)
goto NoLicenseProblem


:NoLicenseAvailable
echo:Error: After %BuildAttempt% attempts, the Flex license still appear to be unavailable. Failing the build!
echo:
popd
exit /b 1

:NoLicenseProblem
:: Parse exit codes
set KnownErrors=0 1 2 3 11 12 13 15 20 41

echo:Kiel compiler exited with error code %ReportedError%

for %%a in (%KnownErrors%) do (
   if [%ReportedError%] equ [%%a] goto Error%ReportedError%
)
goto UnknownError

:Error0
   echo Compilation successful
   goto ExitButContinueJob

:Error1
   echo Warnings were found
   goto ExitButContinueJob

:Error2 
   echo Errors were found
   goto ExitCritical

:Error3
   echo Error 3 = Fatal Errors
   goto ExitCritical

:Error11
   echo Error 11 = Cannot open project file for writing
   goto ExitCritical

:Error12
   echo Error 12 = Device with given name in not found in database
   goto ExitCritical

:Error13
   echo Error 13 = Error writing project file
   goto ExitCritical

:Error15
   echo Error 15 = Error reading import XML file
   goto ExitCritical

:Error20
   echo Error 20 = Can not convert the project file.
   goto ExitCritical

:Error41
   echo Error 41 = Can not create the logfile requested using the -l switch.
   goto ExitCritical

:UnknownError
   echo Error %ReportedError% = Unknown error 
   goto ExitCritical

:ExitCritical
echo:
if [%ReportedError%] neq 0 exit /b %ReportedError% 

:ExitButContinueJob
echo:
popd
exit /b 0

KeiluVisionBuilder.md

Command line compiling with the Keil µVision compiler (at least version 4 and 5)

Compiling your Kiel µVision projects from the commandline should be easy, and out of the box it is resonable simple. However the Commandline interface is very limited and it has basically not changed since 2011.

The KeiluVisionBuilder.cmd batch script attempts to handle the following situations:

• Suppress tge compiler Windows GUI for error reporting; which is especially a probelem when using the compiler on a build server.
• Operates on all the output streams from the compiler; Strangely the Keil uVision compiler creates up to two sets of output: Either none, one, the other or both output files are created.
• When the Flex license server is used, a number of conflicts can occour, so in this script you can:
  • Define a number of times you want to retry a build
  • Set the interval between attempted builds.
  • Successfully recover if the license is suddenly withdrawn during a build.

Originally published in this Stack Overflow answer.

@f-steff thanks for the script. Greatly useful!