Fix KT-39548: workaround MinGW bug with .ctors.65534 section (#4249)

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

@@ -27,6 +27,7 @@ import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
 import org.jetbrains.kotlin.konan.target.CompilerOutputKind
+import org.jetbrains.kotlin.konan.target.Family
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.descriptorUtil.classId
@@ -2353,7 +2354,18 @@ internal class CodeGeneratorVisitor(val context: Context, val lifetimes: Map<IrE
     // Create object { i32, void ()*, i8* } { i32 1, void ()* @ctorFunction, i8* null }
 
     fun createGlobalCtor(ctorFunction: LLVMValueRef): ConstPointer {
-        val priority = kImmInt32One
+        val priority = if (context.config.target.family == Family.MINGW) {
+            // Workaround MinGW bug. Using this value makes the compiler generate
+            // '.ctors' section instead of '.ctors.XXXXX', which can't be recognized by ld
+            // when string table is too long.
+            // More details: https://youtrack.jetbrains.com/issue/KT-39548
+            Int32(65535).llvm
+            // Note: this difference in priorities doesn't actually make initializers
+            // platform-dependent, because handling priorities for initializers
+            // from different object files is platform-dependent anyway.
+        } else {
+            kImmInt32One
+        }
         val data     = kNullInt8Ptr
         val argList  = cValuesOf(priority, ctorFunction, data)
         val ctorItem = LLVMConstNamedStruct(kCtorType, argList, 3)!!

backend.native/tests/build.gradle

@@ -3137,6 +3137,32 @@ task deserialized_listof0(type: KonanLocalTest) {
     source = "serialization/deserialized_listof0.kt"
 }
 
+task genKt39548 {
+    doFirst {
+        GenTestKT39548Kt.genTestKT39548(file("$buildDir/kt39548/kt39548.kt"))
+    }
+}
+
+KotlinNativeTestKt.createTest(project, "kt39548", KonanStandaloneTest) { task ->
+    // Test infrastructure doesn't support generated source;
+    // workaround by specifying dummy source:
+    task.source = "does/not/exist/kt39548.dummy.kt"
+    task.enabled = isWindowsTarget(project)
+
+    if (task.enabled) {
+        konanArtifacts {
+            program(name, targets: [target.name]) {
+                baseDir   "$testOutputLocal/$name"
+                srcFiles  "$buildDir/kt39548/kt39548.kt" // Generated by genKt39548 task.
+                extraOpts task.flags
+                extraOpts project.globalTestArgs
+            }
+        }
+
+        UtilsKt.findKonanBuildTask(project, name, target).dependsOn(genKt39548)
+    }
+}
+
 linkTest("deserialized_members") {
     goldValue=
         "first level\n"+

build-tools/src/main/kotlin/org/jetbrains/kotlin/genTestKT39548.kt

@@ -0,0 +1,37 @@
+package org.jetbrains.kotlin
+
+import java.io.File
+
+fun genTestKT39548(file: File) {
+    val longName = StringBuilder().apply {
+        repeat(10_000_000) {
+            append('a')
+        }
+    }
+
+    val text = """
+            import kotlin.test.*
+
+            fun $longName(): Int = 42
+            fun <T> same(value: T): T = value
+            val globalInt1: Int = same(1)
+            val globalStringA: String = same("a")
+            @ThreadLocal val threadLocalInt2: Int = same(2)
+            @ThreadLocal val threadLocalStringB: String = same("b")
+
+            fun main() {
+                // Ensure function don't get DCEd:
+                val resultOfFunctionWithLongName = $longName()
+                assertEquals(42, resultOfFunctionWithLongName)
+
+                // Check that top-level initializers did run as expected:
+                assertEquals(1, globalInt1)
+                assertEquals("a", globalStringA)
+                assertEquals(2, threadLocalInt2)
+                assertEquals("b", threadLocalStringB)
+            }
+        """.trimIndent()
+
+    file.parentFile.mkdirs()
+    file.writeText(text)
+}