Added explanation

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/Context.kt

@@ -386,6 +386,13 @@ internal class Context(config: KonanConfig) : KonanBackendContext(config) {
         config.configuration.get(KonanConfigKeys.PRODUCE) == CompilerOutputKind.DYNAMIC
     }
 
+    // For wasm32 target we use `llvm-link -internalize` which is kinda broken.
+    // llvm-link links modules one by one and can't see usages
+    // of symbol in subsequent modules. So it will mangle such symbol if
+    // -internalize flag (which is needed for DCE) is provided
+    // That's the case for the stdlib and runtime modules
+    // The solution is to add such symbols to llvm.used array to preserve them from
+    // mangling.
     fun shouldPreserveRuntimeSymbols(): Boolean =
             config.targetManager.target == KonanTarget.WASM32
 }