build: fix how we handle x86_64 library paths

Author: ktoso

BuildLogic/src/main/kotlin/build-logic.java-common-conventions.gradle.kts

@@ -43,19 +43,24 @@ tasks.withType(JavaCompile::class).forEach {
 }
 
 
+// FIXME: cannot share definition with 'buildSrc' so we duplicated the impl here
 fun javaLibraryPaths(): List<String> {
     val osName = System.getProperty("os.name")
     val osArch = System.getProperty("os.arch")
     val isLinux = osName.lowercase(Locale.getDefault()).contains("linux")
 
     return listOf(
-        if (osName.lowercase(Locale.getDefault()).contains("linux")) {
-            """$rootDir/.build/$osArch-unknown-linux-gnu/debug/"""
+        if (isLinux) {
+            if (osArch.equals("x86_64") || osArch.equals("amd64")) {
+                "$rootDir/.build/x86_64-unknown-linux-gnu/debug/"
+            } else {
+                "$rootDir/.build/$osArch-unknown-linux-gnu/debug/"
+            }
         } else {
             if (osArch.equals("aarch64")) {
-                """$rootDir/.build/arm64-apple-macosx/debug/"""
+                "$rootDir/.build/arm64-apple-macosx/debug/"
             } else {
-                """$rootDir/.build/$osArch-apple-macosx/debug/"""
+                "$rootDir/.build/$osArch-apple-macosx/debug/"
             }
         },
         if (isLinux) {

buildSrc/README.md

@@ -0,0 +1 @@
+buildSrc are shared "build library code" that is available to all sub-projects of the primary build. 

buildSrc/build.gradle

@@ -1,3 +1,17 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
 repositories {
     mavenCentral()
 }

buildSrc/src/main/groovy/org/swift/swiftkit/gradle/BuildUtils.groovy

@@ -15,17 +15,21 @@
 package org.swift.swiftkit.gradle
 
 final class BuildUtils {
+
+    /// Find library paths for 'java.library.path' when running or testing projects inside this build.
     static def javaLibraryPaths(File rootDir) {
         def osName = System.getProperty("os.name")
         def osArch = System.getProperty("os.arch")
         def isLinux = osName.toLowerCase(Locale.getDefault()).contains("linux")
 
         return [
-                osName.toLowerCase(Locale.getDefault()).contains("linux") ?
-                        "${rootDir}/.build/${osArch}-unknown-linux-gnu/debug/" :
-                        osArch == "aarch64" ?
+                isLinux ?
+                        /* Linux */(osArch == "amd64" || osArch == "amd64" ?
+                                "${rootDir}/.build/x86_64-unknown-linux-gnu/debug/" :
+                                "${rootDir}/.build/${osArch}-unknown-linux-gnu/debug/") :
+                        /* macOS */(osArch == "aarch64" ?
                                 "${rootDir}/.build/arm64-apple-macosx/debug/" :
-                                "${rootDir}/.build/${osArch}-apple-macosx/debug/",
+                                "${rootDir}/.build/${osArch}-apple-macosx/debug/"),
                 isLinux ?
                         "/usr/lib/swift/linux" :
                         // assume macOS