[K/N] Fix building mimalloc with TSAN

kotlin-native/build-tools/src/main/kotlin/org/jetbrains/kotlin/bitcode/CompileToBitcode.kt

@@ -102,6 +102,9 @@ abstract class CompileToBitcode @Inject constructor(
     @Input @Optional
     var sanitizer: SanitizerKind? = null
 
+    @Input @Optional
+    val extraSanitizerArgs = mutableMapOf<SanitizerKind, List<String>>()
+
     private val targetDir: File
         get() {
             val sanitizerSuffix = when (sanitizer) {
@@ -136,11 +139,18 @@ abstract class CompileToBitcode @Inject constructor(
                 null -> listOf()
                 SanitizerKind.ADDRESS -> listOf("-fsanitize=address")
                 SanitizerKind.THREAD -> listOf("-fsanitize=thread")
-            }
+            } + (extraSanitizerArgs[sanitizer] ?: emptyList())
             val languageFlags = when (language) {
-                Language.C ->
-                    // Used flags provided by original build of allocator C code.
-                    listOf("-std=gnu11", "-O3", "-Wall", "-Wextra", "-Werror")
+                Language.C -> {
+                    listOf("-std=gnu11", "-Wall", "-Wextra", "-Werror") +
+                    if (sanitizer != SanitizerKind.THREAD) {
+                        // Used flags provided by original build of allocator C code.
+                        listOf("-O3")
+                    } else {
+                        // Building with TSAN needs turning off extra optimizations.
+                        listOf("-O1")
+                    }
+                }
                 Language.CPP ->
                     listOfNotNull("-std=c++17", "-Werror", "-O2",
                             "-fno-aligned-allocation", // TODO: Remove when all targets support aligned allocation in C++ runtime.

kotlin-native/runtime/build.gradle.kts

@@ -77,6 +77,7 @@ bitcode {
         compilerArgs.addAll(listOf("-DKONAN_MI_MALLOC=1", "-Wno-unknown-pragmas", "-ftls-model=initial-exec",
                 "-Wno-unused-function", "-Wno-error=atomic-alignment",
                 "-Wno-unused-parameter" /* for windows 32*/))
+        extraSanitizerArgs[SanitizerKind.THREAD] = listOf("-DMI_TSAN=1")
         headersDirs = files("$srcRoot/c/include")
 
         onlyIf { targetSupportsMimallocAllocator(target) }