ci: refresh Windows ARM64 toolchain pins

.github/workflows/architectures.yml

@@ -29,7 +29,7 @@ jobs:
             -Uri 'https://download.racket-lang.org/installers/9.3/racket-9.3-arm64-win32-cs.exe' `
             -OutFile $installer
           $hash = (Get-FileHash $installer -Algorithm SHA256).Hash.ToLowerInvariant()
-          if ($hash -ne 'fcccd112afd3c8fecfdaf56d2a2fc3213fe006d8e4eac525ceaee56f10628a01') {
+          if ($hash -ne '15cd4ace652427465c7c576bad4aede2b8519cb6b59b190c9a22862cf57e7924') {
             throw "Racket 9.3 arm64 installer checksum mismatch: $hash"
           }
           # NSIS silent install; /D must be last and unquoted. On Windows the

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+- Prefer native 64-bit MSBuild when discovering Visual Studio, preventing the
+  32-bit host compiler from exhausting its address space on WinUI ARM64 builds.
 - Add the Linux tray contract: `rivet::system::TrayIcon` hosts an
   org.kde.StatusNotifierItem with a com.canonical.dbusmenu menu over the
   session bus (GDBus), the pairing every desktop watcher serves (GNOME via

rivet-cli/windows-tools.rkt

@@ -66,13 +66,25 @@
        #:key path->string)
       '()))
 
+(define (prefer-64-bit-msbuild executable)
+  (and executable
+       (or (existing-file
+            (build-path (path-only executable) "amd64" "MSBuild.exe"))
+           executable)))
+
 (define (msbuild-in-installation root)
   (and root
        (let ([msbuild-root (build-path root "MSBuild")])
-         (or (existing-file
-              (build-path msbuild-root "Current" "Bin" "MSBuild.exe"))
+         (define (in-bin bin)
+           ;; The native 64-bit MSBuild selects Hostx64 compiler tools for
+           ;; cross-targets. The generic executable can select HostX86 even
+           ;; when PreferredToolArchitecture=x64 is passed, exhausting its
+           ;; address space while compiling WinUI generated sources.
+           (or (existing-file (build-path bin "amd64" "MSBuild.exe"))
+               (existing-file (build-path bin "MSBuild.exe"))))
+         (or (in-bin (build-path msbuild-root "Current" "Bin"))
              (for/or ([entry (in-list (sorted-child-directories msbuild-root))])
-               (existing-file (build-path entry "Bin" "MSBuild.exe")))))))
+               (in-bin (build-path entry "Bin")))))))
 
 (define (vc-toolset-in-installation root)
   (and root
@@ -101,7 +113,9 @@
 (define (discover-windows-toolchain)
   (define vswhere (candidate-vswhere))
 
-  (define path-msbuild (existing-file (find-executable-path "MSBuild.exe")))
+  (define path-msbuild
+    (prefer-64-bit-msbuild
+     (existing-file (find-executable-path "MSBuild.exe"))))
   (define path-cl (existing-file (find-executable-path "cl.exe")))
   (define path-lib (existing-file (find-executable-path "lib.exe")))
   (define path-dumpbin (existing-file (find-executable-path "dumpbin.exe")))
@@ -149,5 +163,6 @@
 
 (module+ test-support
   (provide msbuild-in-installation
+           prefer-64-bit-msbuild
            vc-toolset-in-installation
            sorted-child-directories))

tests/windows-tools.rkt

@@ -41,17 +41,30 @@
     (touch (build-path unexpected "dumpbin.exe"))
     (check-equal? (vc-toolset-in-installation temp-root) expected-vc)
 
-    ;; Prefer Visual Studio's stable Current alias for MSBuild.
+    ;; Prefer the native 64-bit executable under Visual Studio's stable
+    ;; Current alias; the generic executable can select HostX86 tools.
+    (touch (build-path temp-root "MSBuild" "Current" "Bin" "MSBuild.exe"))
     (define current-msbuild
-      (touch (build-path temp-root "MSBuild" "Current" "Bin" "MSBuild.exe")))
+      (touch
+       (build-path temp-root "MSBuild" "Current" "Bin" "amd64" "MSBuild.exe")))
     (touch (build-path temp-root "MSBuild" "18.0" "Bin" "MSBuild.exe"))
     (check-equal? (msbuild-in-installation temp-root) current-msbuild)
 
+    ;; Apply the same upgrade when a generic MSBuild executable is already on
+    ;; PATH, instead of letting PATH bypass installation discovery.
+    (define path-bin (build-path temp-root "path-bin"))
+    (define path-msbuild (touch (build-path path-bin "MSBuild.exe")))
+    (define path-amd64-msbuild
+      (touch (build-path path-bin "amd64" "MSBuild.exe")))
+    (check-equal? (prefer-64-bit-msbuild path-msbuild) path-amd64-msbuild)
+
     ;; Without Current, choose the newest bounded MSBuild directory.
     (define fallback-root (build-path temp-root "fallback"))
     (touch (build-path fallback-root "MSBuild" "17.0" "Bin" "MSBuild.exe"))
+    (touch (build-path fallback-root "MSBuild" "18.0" "Bin" "MSBuild.exe"))
     (define newest-msbuild
-      (touch (build-path fallback-root "MSBuild" "18.0" "Bin" "MSBuild.exe")))
+      (touch
+       (build-path fallback-root "MSBuild" "18.0" "Bin" "amd64" "MSBuild.exe")))
     (check-equal? (msbuild-in-installation fallback-root) newest-msbuild)
 
     (define children