From 3cfc0169e34bbe6fca99e4d2f357004e9275c602 Mon Sep 17 00:00:00 2001
From: Zach Vorhies <zachvorhies@protonmail.com>
Date: Mon, 2 Nov 2026 13:55:07 -0800
Subject: [PATCH 1/2] ci(build): build x86_64 Linux natively so pkg-config
 finds system GTK (#285)

---
 .github/workflows/_build.yml | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/_build.yml b/.github/workflows/_build.yml
index e107e26e..fcaada0a 100644
--- a/.github/workflows/_build.yml
+++ b/.github/workflows/_build.yml
@@ -110,15 +110,22 @@ jobs:
           linker: platform-default
           toolchain-file: rust-toolchain.ci.toml
 
+      # x86_64-unknown-linux-gnu is the runner's own triple, so it builds
+      # natively, without `--target`. Naming it makes soldr switch to its
+      # glibc-2.17 catalogue sysroot and point PKG_CONFIG_LIBDIR there, which
+      # hides Ubuntu's GTK/WebKit from pkg-config, so glib-sys fails (#285).
+      # The artifact names and wheel plat tag still use inputs.rust-target.
       - name: Build fastled CLI binary (for wheel bundling)
+        env:
+          CARGO_TARGET_TRIPLE: ${{ inputs.rust-target != 'x86_64-unknown-linux-gnu' && inputs.rust-target || '' }}
         run: |
-          if [ -n "${{ inputs.rust-target }}" ]; then
-            soldr cargo build --release --bin fastled --target "${{ inputs.rust-target }}"
-            case "${{ inputs.rust-target }}" in
+          if [ -n "$CARGO_TARGET_TRIPLE" ]; then
+            soldr cargo build --release --bin fastled --target "$CARGO_TARGET_TRIPLE"
+            case "$CARGO_TARGET_TRIPLE" in
               *windows*) EXE_NAME="fastled.exe" ;;
               *)         EXE_NAME="fastled" ;;
             esac
-            BIN_SRC="target/${{ inputs.rust-target }}/release/${EXE_NAME}"
+            BIN_SRC="target/$CARGO_TARGET_TRIPLE/release/${EXE_NAME}"
           else
             soldr cargo build --release --bin fastled
             case "$(uname -s)" in
@@ -174,7 +181,8 @@ jobs:
         env:
           # setup.py rebuilds the bundled binary; keep that rebuild on the
           # requested target, especially Windows ARM on an x64 runner.
-          FASTLED_RUST_TARGET: ${{ inputs.rust-target }}
+          # Native for x86_64 Linux, for the same reason as the build step.
+          FASTLED_RUST_TARGET: ${{ inputs.rust-target != 'x86_64-unknown-linux-gnu' && inputs.rust-target || '' }}
         run: |
           PLAT_NAME=""
           case "${{ inputs.rust-target }}" in

From 29b41abcaccb7f8d20ef0f523a646e70c3011e2a Mon Sep 17 00:00:00 2001
From: Zach Vorhies <zachvorhies@protonmail.com>
Date: Mon, 2 Nov 2026 14:09:31 -0800
Subject: [PATCH 2/2] test(ci): pin the native x86_64 Linux build contract
 (#285)

---
 tests/unit/test_ci_modes.py | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/tests/unit/test_ci_modes.py b/tests/unit/test_ci_modes.py
index ce82543c..cf7555f6 100644
--- a/tests/unit/test_ci_modes.py
+++ b/tests/unit/test_ci_modes.py
@@ -380,7 +380,25 @@ def test_cross_target_wheel_build_preserves_target_for_setup_py():
     wheel_step = build.split("      - name: Build wheel\n", 1)[1].split(
         "      - name: Smoke test", 1
     )[0]
-    assert "FASTLED_RUST_TARGET: ${{ inputs.rust-target }}" in wheel_step
+    # Cross targets keep their triple; only the runner-native x86_64 Linux
+    # triple is dropped so soldr does not swap in its glibc-2.17 sysroot (#285).
+    native = "inputs.rust-target != 'x86_64-unknown-linux-gnu'"
+    assert (
+        f"FASTLED_RUST_TARGET: ${{{{ {native} && inputs.rust-target || '' }}}}"
+        in wheel_step
+    )
+
+
+def test_native_x86_linux_build_omits_target_so_pkg_config_sees_system_gtk():
+    build = (WORKFLOWS / "_build.yml").read_text()
+    step = build.split("      - name: Build fastled CLI binary", 1)[1].split(
+        "      - name: Build wheel", 1
+    )[0]
+    assert (
+        "CARGO_TARGET_TRIPLE: ${{ inputs.rust-target != "
+        "'x86_64-unknown-linux-gnu' && inputs.rust-target || '' }}"
+    ) in step
+    assert '--target "$CARGO_TARGET_TRIPLE"' in step
 
 
 def test_release_report_validation_rejects_missing_or_wrong_sha_cells():