diff --git a/build.gradle.kts b/build.gradle.kts
index cb474bf66bf..971679c1dc2 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -470,7 +470,7 @@ allprojects {
         }
     }
 
-    if (!kotlinBuildProperties.isInJpsBuildIdeaSync) {
+    if (!kotlinBuildProperties.isInJpsBuildIdeaSync && !kotlinBuildProperties.useFir) {
         // For compiler and stdlib, allWarningsAsErrors is configured in the corresponding "root" projects
         // (compiler/build.gradle.kts and libraries/commonConfiguration.gradle).
         val projectsWithWarningsAsErrors = listOf("core", "plugins").map { File(it).absoluteFile }