Try a different approach

Author: znicholls

.github/workflows/install-pypi.yaml

@@ -27,19 +27,21 @@ jobs:
         python-version: [ "3.9", "3.10", "3.11", "3.12", "3.13" ]
         # Check both 'library' install and the 'application' (i.e. locked) install
         install-target: ["example-fgen-basic", "example-fgen-basic[locked]"]
-        toolchain:
-          # TODO: consider adding other compilers to our matrix
-          # (see https://github.com/fortran-lang/setup-fortran)
-          - {compiler: gcc, version: 13}
-          # # Only seems to be available on Mac for some reason,
-          # # maybe it will be available when latest images are updated.
-          # - {compiler: gcc, version: 15}
         pip-install-flags: ["--only-binary example-fgen-basic"]
         include:
           # Source installs on all OS for a stable Python version
           # (no need to do more than this)
-          - pip-install-flags: "--no-binary example-fgen-basic"
+          - os: ["ubuntu-latest", "macos-latest", "windows-latest"]
             python-version: "3.11"
+            install-target: ["example-fgen-basic", "example-fgen-basic[locked]"]
+            pip-install-flags: "--no-binary example-fgen-basic"
+            toolchain:
+              # TODO: consider adding other compilers to our matrix
+              # (see https://github.com/fortran-lang/setup-fortran)
+              - {compiler: gcc, version: 13}
+              # # Only seems to be available on Mac for some reason,
+              # # maybe it will be available when latest images are updated.
+              # - {compiler: gcc, version: 15}
 
     steps:
     - name: Set up Python "${{ matrix.python-version }}"
@@ -58,7 +60,7 @@ jobs:
     - name: Install
       run: |
         pip install --upgrade pip wheel
-        pip install "${{ matrix.install-target }}"
+        pip install "${{ matrix.install-target }}" ${{ matrix.pip-install-flags }}
     - name: Check no warnings
       if: matrix.os != 'windows-latest'
       run: |