From 521901f09a92d878c597026154db0d8da148c8a3 Mon Sep 17 00:00:00 2001
From: Mikhail Glukhikh <mikhail.glukhikh@jetbrains.com>
Date: Fri, 3 Jul 2020 18:07:24 +0300
Subject: [PATCH] [FIR2IR] Cache type parameters for existing IR classes
 properly

Before this commit, we just recreated class header
for external IR class found by signature. However, it's not required,
because super-types, type parameters, etc. are already initialized.
So now we just read type parameters and build cache for them.
---
 .../jetbrains/kotlin/fir/backend/Fir2IrClassifierStorage.kt  | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrClassifierStorage.kt b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrClassifierStorage.kt
index 8f34024f34e..37a0e26ede6 100644
--- a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrClassifierStorage.kt
+++ b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrClassifierStorage.kt
@@ -429,7 +429,10 @@ class Fir2IrClassifierStorage(
         symbolTable.referenceClassIfAny(signature)?.let { irClassSymbol ->
             val irClass = irClassSymbol.owner
             classCache[firClass as FirRegularClass] = irClass
-            processClassHeader(firClass, irClass)
+            val mappedTypeParameters = firClass.typeParameters.filterIsInstance<FirTypeParameter>().zip(irClass.typeParameters)
+            for ((firTypeParameter, irTypeParameter) in mappedTypeParameters) {
+                typeParameterCache[firTypeParameter] = irTypeParameter
+            }
             declarationStorage.preCacheBuiltinClassMembers(firClass, irClass)
             return irClassSymbol
         }