Fix the SDK builds when the build arch isn't the first in WindowsSDKs

This fixes it so that the built compiler to run with the pinned
runtime in building some of the SDK components so that the build
doesn't fail due to yet-to-be-built runtimes even when the build arch
isn't the first in the WindowsSDKs list.

Author: hjyamauchi

utils/build.ps1

@@ -171,9 +171,9 @@ if ($PinnedBuild -eq "") {
       $PinnedVersion = "6.0.3"
     }
     "ARM64" {
-      $PinnedBuild = "https://download.swift.org/swift-6.0.3-release/windows10-arm64/swift-6.0.3-RELEASE/swift-6.0.3-RELEASE-windows10-arm64.exe"
-      $PinnedSHA256 = "81474651E59A9955C9E6A389EF53ABD61631FFC62C63A2A02977271019E7C722"
-      $PinnedVersion = "6.0.3"
+      $PinnedBuild = "https://github.com/thebrowsercompany/swift-build/releases/download/swift-6.0.0-20241216.0/installer-arm64.exe"
+      $PinnedSHA256 = "9007ABBA15E863206C35EDA3285CD31F9196E81C046DBA911E76282E78F3103F"
+      $PinnedVersion = "6.0.0"
     }
     default { throw "Unsupported processor architecture" }
   }
@@ -1858,16 +1858,20 @@ function Build-Dispatch([Platform]$Platform, $Arch, [switch]$Test = $false) {
     $InstallPath = "$($Arch.SDKInstallRoot)\usr"
   }
 
-  Build-CMakeProject `
-    -Src $SourceCache\swift-corelibs-libdispatch `
-    -Bin (Get-TargetProjectBinaryCache $Arch Dispatch) `
-    -InstallTo $InstallPath `
-    -Arch $Arch `
-    -Platform $Platform `
-    -UseBuiltCompilers C,CXX,Swift `
-    -Defines @{
-      ENABLE_SWIFT = "YES";
-    }
+  Isolate-EnvVars {
+    $env:Path = "$(Get-CMarkBinaryCache $BuildArch)\src;$(Get-PinnedToolchainRuntime);${env:Path}"
+
+    Build-CMakeProject `
+      -Src $SourceCache\swift-corelibs-libdispatch `
+      -Bin (Get-TargetProjectBinaryCache $Arch Dispatch) `
+      -InstallTo $InstallPath `
+      -Arch $Arch `
+      -Platform $Platform `
+      -UseBuiltCompilers C,CXX,Swift `
+      -Defines @{
+        ENABLE_SWIFT = "YES";
+      }
+  }
 }
 
 function Build-Foundation([Platform]$Platform, $Arch, [switch]$Test = $false) {
@@ -1919,6 +1923,8 @@ function Build-Foundation([Platform]$Platform, $Arch, [switch]$Test = $false) {
         (Get-Variable "${Platform}$($Arch.ShortName)" -ValueOnly).SDKInstallRoot
       }
 
+      $env:Path = "$(Get-CMarkBinaryCache $BuildArch)\src;$(Get-PinnedToolchainRuntime);${env:Path}"
+
       Build-CMakeProject `
         -Src $SourceCache\swift-corelibs-foundation `
         -Bin $FoundationBinaryCache `
@@ -1969,7 +1975,7 @@ function Build-FoundationMacros() {
 
   $SwiftSDK = $null
   if ($Build) {
-    $SwiftSDK = $BuildArch.SDKInstallRoot
+    $SwiftSDK = $(Get-PinnedToolchainSDK)
   }
 
   $InstallDir = $null
@@ -1985,18 +1991,24 @@ function Build-FoundationMacros() {
     Get-HostProjectCMakeModules Compilers
   }
 
-  Build-CMakeProject `
-    -Src $SourceCache\swift-foundation\Sources\FoundationMacros `
-    -Bin $FoundationMacrosBinaryCache `
-    -InstallTo:$InstallDir `
-    -Arch $Arch `
-    -Platform $Platform `
-    -UseBuiltCompilers Swift `
-    -SwiftSDK:$SwiftSDK `
-    -BuildTargets:$Targets `
-    -Defines @{
-      SwiftSyntax_DIR = $SwiftSyntaxCMakeModules;
+  Isolate-EnvVars {
+    if ($Build) {
+      $env:Path = "$(Get-CMarkBinaryCache $BuildArch)\src;$(Get-PinnedToolchainRuntime);${env:Path}"
     }
+
+    Build-CMakeProject `
+      -Src $SourceCache\swift-foundation\Sources\FoundationMacros `
+      -Bin $FoundationMacrosBinaryCache `
+      -InstallTo:$InstallDir `
+      -Arch $Arch `
+      -Platform $Platform `
+      -UseBuiltCompilers Swift `
+      -SwiftSDK:$SwiftSDK `
+      -BuildTargets:$Targets `
+      -Defines @{
+        SwiftSyntax_DIR = $SwiftSyntaxCMakeModules;
+      }
+  }
 }
 
 function Build-XCTest([Platform]$Platform, $Arch, [switch]$Test = $false) {
@@ -2020,6 +2032,7 @@ function Build-XCTest([Platform]$Platform, $Arch, [switch]$Test = $false) {
       $TestingDefines = @{ ENABLE_TESTING = "NO" }
       $Targets = @("install")
       $InstallPath = "$($Arch.XCTestInstallRoot)\usr"
+      $env:Path = "$(Get-CMarkBinaryCache $BuildArch)\src;$(Get-PinnedToolchainRuntime);${env:Path}"
     }
 
     Build-CMakeProject `
@@ -2051,6 +2064,8 @@ function Build-Testing([Platform]$Platform, $Arch, [switch]$Test = $false) {
       $InstallPath = "$($Arch.SwiftTestingInstallRoot)\usr"
     }
 
+    $env:Path = "$(Get-CMarkBinaryCache $BuildArch)\src;$(Get-PinnedToolchainRuntime);${env:Path}"
+
     Build-CMakeProject `
       -Src $SourceCache\swift-testing `
       -Bin $SwiftTestingBinaryCache `
@@ -2605,7 +2620,7 @@ function Build-TestingMacros() {
 
   $SwiftSDK = $null
   if ($Build) {
-    $SwiftSDK = $BuildArch.SDKInstallRoot
+    $SwiftSDK = $(Get-PinnedToolchainSDK)
   }
 
   $Targets = if ($Build) {
@@ -2627,18 +2642,24 @@ function Build-TestingMacros() {
     Get-HostProjectCMakeModules Compilers
   }
 
-  Build-CMakeProject `
-    -Src $SourceCache\swift-testing\Sources\TestingMacros `
-    -Bin $TestingMacrosBinaryCache `
-    -InstallTo:$InstallDir  `
-    -Arch $Arch `
-    -Platform $Platform `
-    -UseBuiltCompilers Swift `
-    -SwiftSDK:$SwiftSDK `
-    -BuildTargets:$Targets `
-    -Defines @{
-      SwiftSyntax_DIR = $SwiftSyntaxCMakeModules;
+  Isolate-EnvVars {
+    if ($Build) {
+      $env:Path = "$(Get-CMarkBinaryCache $BuildArch)\src;$(Get-PinnedToolchainRuntime);${env:Path}"
     }
+
+    Build-CMakeProject `
+      -Src $SourceCache\swift-testing\Sources\TestingMacros `
+      -Bin $TestingMacrosBinaryCache `
+      -InstallTo:$InstallDir  `
+      -Arch $Arch `
+      -Platform $Platform `
+      -UseBuiltCompilers Swift `
+      -SwiftSDK:$SwiftSDK `
+      -BuildTargets:$Targets `
+      -Defines @{
+        SwiftSyntax_DIR = $SwiftSyntaxCMakeModules;
+      }
+  }
 }
 
 function Install-HostToolchain() {