out of nowhere this error happens when I try to bu...

# announcements

[david.bilik]

out of nowhere this error happens when I try to build project

Error:(5, 0) For input string: ""
Open File

Nothing changes and the line in build.gradle is apply plugin: ‘kotlin-android’. The stacktrace of error says

Failed to notify ProjectEvaluationListener.afterEvaluate(), but primary configuration failure takes precedence.
java.lang.IllegalStateException: buildToolsVersion is not specified.

Of course my build tools version is set
If i build my project with —stacktrace option, this is what is printed in console

Caused by: java.lang.NumberFormatException: For input string: ""
  at org.jetbrains.kotlin.incremental.CacheVersion.getActualVersion(
  at org.jetbrains.kotlin.incremental.CacheVersion.checkVersion(
  at org.jetbrains.kotlin.incremental.BuildCacheStorage.<init>(
  at org.jetbrains.kotlin.gradle.plugin.KotlinGradleBuildServices.<init>(

  at org.jetbrains.kotlin.gradle.plugin.KotlinGradleBuildServices.<init>(

  at org.jetbrains.kotlin.gradle.plugin.KotlinGradleBuildServices$Companion

  at org.jetbrains.kotlin.gradle.plugin.KotlinBasePluginWrapper.apply(

  at org.jetbrains.kotlin.gradle.plugin.KotlinBasePluginWrapper.apply(

  at org.gradle.api.internal.plugins.ImperativeOnlyPluginApplicator.

  at org.gradle.api.internal.plugins.RuleBasedPluginApplicator.

  at org.gradle.api.internal.plugins.DefaultPluginManager.doApply(

  ... 72 more

[david.bilik]

Manual clean (delete build folders) solved that issue