fix: SDK compiler defaults, library extraction, and Windows esptool

.github/workflows/check-ubuntu.yml

@@ -103,6 +103,10 @@ jobs:
       - name: Test
         id: tests
         run: uv run --no-project python ci/test_cache_status.py -- soldr cargo test --workspace
+      - name: Test optional SDK library linkage with native GCC LTO
+        run: |
+          soldr cargo test -p fbuild-build-engine --lib optional_framework_archive_preserves_only_referenced_initializers -- --ignored
+          soldr cargo test -p fbuild-build-arm --lib optional_library_rescans_earlier_dependency_archive -- --ignored
 
   python-facade-tests:
     # FastLED/fbuild#1485 §5.2/§6: the embedded-CPython AT-P integration

.github/workflows/check-windows.yml

@@ -118,3 +118,52 @@ jobs:
             throw "Warm check did not reuse the verified source launcher"
           }
           # The hosted runner discards RUNNER_TEMP after the job.
+
+      # Pioarduino 55.03.35 pins esptool 5.1.0, whose release has no
+      # Windows standalone binary. Verify the real source-package route.
+      - name: Install and recheck ESP32-C6 source tools
+        id: modern-esptool
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = "Stop"
+          $probe = Join-Path $env:RUNNER_TEMP ("fbuild-modern-esptool-" + [guid]::NewGuid())
+          New-Item -ItemType Directory -Path $probe | Out-Null
+          $env:FBUILD_CACHE_DIR = Join-Path $probe "cache"
+          [Environment]::SetEnvironmentVariable("FBUILD_ESPTOOL_PATH", $null, "Process")
+          @"
+          [env:esp32c6-idf5]
+          platform = https://github.com/pioarduino/platform-espressif32/releases/download/55.03.35/platform-espressif32.zip
+          board = esp32-c6-devkitc-1
+          framework = arduino
+          "@ | Set-Content -LiteralPath (Join-Path $probe "platformio.ini") -Encoding utf8
+
+          $coldJson = & soldr cargo run -p fbuild-cli --bin fbuild -- install "$probe" -e esp32c6-idf5 --json
+          if ($LASTEXITCODE -ne 0) { throw "Cold ESP32-C6 install failed ($LASTEXITCODE)" }
+          $coldJson | Write-Output
+          $cold = ($coldJson -join "`n") | ConvertFrom-Json
+          $coldTools = @($cold.environments.packages | Where-Object name -eq "tool-esptoolpy")
+          if ($coldTools.Count -ne 1) { throw "Expected exactly one esptool package" }
+          $coldTool = $coldTools[0]
+          if ($coldTool.version -ne "5.1.0" -or $coldTool.status -ne "fetched" -or
+              $coldTool.url -ne "https://github.com/pioarduino/esptool/releases/download/v5.1.0/esptool.zip") {
+            throw "Expected a cold install of the pinned esptool 5.1.0 source archive"
+          }
+          if (-not (Test-Path -LiteralPath $coldTool.install_path -PathType Leaf)) {
+            throw "Installed esptool launcher is missing"
+          }
+          if ($coldTool.install_path -notmatch '[\\/]\.fbuild-tools[\\/]esptool[\\/]Scripts[\\/]esptool\.exe$') {
+            throw "Expected the real uv-managed Windows esptool launcher"
+          }
+
+          $warmJson = & soldr cargo run -p fbuild-cli --bin fbuild -- install "$probe" -e esp32c6-idf5 --check --json
+          if ($LASTEXITCODE -ne 0) { throw "Warm ESP32-C6 check failed ($LASTEXITCODE)" }
+          $warmJson | Write-Output
+          $warm = ($warmJson -join "`n") | ConvertFrom-Json
+          $warmTools = @($warm.environments.packages | Where-Object name -eq "tool-esptoolpy")
+          if ($warmTools.Count -ne 1) { throw "Expected exactly one cached esptool package" }
+          $warmTool = $warmTools[0]
+          if ($warmTool.version -ne "5.1.0" -or $warmTool.status -ne "present" -or
+              $warmTool.url -ne $coldTool.url -or $warmTool.install_path -ne $coldTool.install_path) {
+            throw "Warm check did not reuse the verified source launcher"
+          }
+          # The hosted runner discards RUNNER_TEMP after the job.

Cargo.toml

@@ -93,7 +93,7 @@ targets = [
 ]
 
 [workspace.package]
-version = "2.5.40"
+version = "2.5.41"
 edition = "2021"
 rust-version = "1.95.0"
 license = "AGPL-3.0-only"

ci/test_fractional_workflows.py

@@ -13,6 +13,31 @@
 
 
 class FractionalWorkflowTests(unittest.TestCase):
+    def test_windows_checks_real_modern_esptool_source_install(self):
+        job = self.load("check-windows.yml")["jobs"]["check"]
+        smoke = next(step for step in job["steps"] if step.get("id") == "modern-esptool")
+        self.assertEqual("windows-latest", job["runs-on"])
+        self.assertEqual("pwsh", smoke["shell"])
+        self.assertNotIn("if", smoke)
+        self.assertFalse(smoke.get("continue-on-error", False))
+        script = smoke["run"]
+        for contract in (
+            "$env:RUNNER_TEMP", "[guid]::NewGuid()", "$env:FBUILD_CACHE_DIR",
+            'SetEnvironmentVariable("FBUILD_ESPTOOL_PATH", $null, "Process")',
+            "https://github.com/pioarduino/platform-espressif32/releases/download/55.03.35/platform-espressif32.zip",
+            "board = esp32-c6-devkitc-1", "framework = arduino",
+            "soldr cargo run -p fbuild-cli --bin fbuild -- install",
+            "--check --json", "$LASTEXITCODE -ne 0", "ConvertFrom-Json",
+            'name -eq "tool-esptoolpy"', 'version -ne "5.1.0"',
+            'status -ne "fetched"', 'status -ne "present"',
+            "https://github.com/pioarduino/esptool/releases/download/v5.1.0/esptool.zip",
+            'Test-Path -LiteralPath $coldTool.install_path -PathType Leaf',
+            '$warmTool.install_path -ne $coldTool.install_path',
+        ):
+            self.assertIn(contract, script)
+        self.assertEqual(2, script.count("soldr cargo run -p fbuild-cli --bin fbuild -- install"))
+        self.assertEqual(2, script.count("$LASTEXITCODE -ne 0"))
+
     def test_macos_lipo_places_input_before_variadic_architectures(self):
         job = self.load("release-auto.yml")["jobs"]["macos-release-smoke"]
         script = next(step["run"] for step in job["steps"] if "lipo " in step.get("run", ""))