dist.yml (Build platform wheels Linux): Use --prefix in /host

.github/workflows/dist.yml

@@ -184,7 +184,7 @@ jobs:
       # https://cibuildwheel.readthedocs.io/en/stable/options/#requires-python
       CIBW_PROJECT_REQUIRES_PYTHON: ">=3.9, <3.13"
       # Environment during wheel build
-      CIBW_ENVIRONMENT: "PATH=$(pwd)/local/bin:$PATH CPATH=$(pwd)/local/include:$CPATH LIBRARY_PATH=$(pwd)/local/lib:$LIBRARY_PATH PKG_CONFIG_PATH=$(pwd)/local/share/pkgconfig:$PKG_CONFIG_PATH ACLOCAL_PATH=/usr/share/aclocal PIP_CONSTRAINT=$(pwd)/constraints.txt"
+      CIBW_ENVIRONMENT: "PATH=$(pwd)/prefix/bin:$PATH CPATH=$(pwd)/prefix/include:$CPATH LIBRARY_PATH=$(pwd)/prefix/lib:$LIBRARY_PATH PKG_CONFIG_PATH=$(pwd)/prefix/share/pkgconfig:$PKG_CONFIG_PATH ACLOCAL_PATH=/usr/share/aclocal PIP_CONSTRAINT=$(pwd)/constraints.txt"
       # Use 'build', not 'pip wheel'
       CIBW_BUILD_FRONTEND: build
     steps:
@@ -207,15 +207,18 @@ jobs:
         # We build the wheels from the sdists so that MANIFEST filtering becomes effective.
         # But we must run cibuildwheel with the unpacked source directory, not a tarball,
         # so that SAGE_ROOT is copied into the build containers.
+        # TODO: Not true any more since https://cibuildwheel.pypa.io/en/stable/changelog/#v250
         #
         # In the CIBW_BEFORE_ALL phase, we install libraries using the Sage distribution.
         # https://cibuildwheel.readthedocs.io/en/stable/options/#before-all
-        # This is unfortunately repeated for each of the packages that we build wheels for
+        # For Linux, this is repeated for each of the packages that we build wheels for
         # because CIBW starts with a fresh container on each invocation.
+        # Therefore we cache it in a directory mounted from the host: /host
+        # https://cibuildwheel.pypa.io/en/stable/faq/#linux-builds-in-containers
         run: |
           "${{ steps.python.outputs.python-path }}" -m pip install pipx
           export PATH=build/bin:$PATH
-          export CIBW_BEFORE_ALL="( $(sage-print-system-package-command debian --yes --no-install-recommends install $(sage-get-system-packages debian $SPKGS)) || $(sage-print-system-package-command fedora --yes --no-install-recommends install $(sage-get-system-packages fedora $SPKGS | sed s/pkg-config/pkgconfig/)) || ( $(sage-print-system-package-command homebrew --yes --no-install-recommends install $(sage-get-system-packages homebrew $SPKGS)) || echo error ignored) ) && ./bootstrap && ./configure --enable-build-as-root && MAKE=\"make -j6\" make V=0 $TARGETS_PRE && (echo \"sage_conf @ file://\$(pwd)/pkgs/sage-conf\" && echo \"sage_setup @ file://\$(pwd)/pkgs/sage-setup\") > constraints.txt"
+          export CIBW_BEFORE_ALL="( $(sage-print-system-package-command debian --yes --no-install-recommends install $(sage-get-system-packages debian $SPKGS)) || $(sage-print-system-package-command fedora --yes --no-install-recommends install $(sage-get-system-packages fedora $SPKGS | sed s/pkg-config/pkgconfig/)) || ( $(sage-print-system-package-command homebrew --yes --no-install-recommends install $(sage-get-system-packages homebrew $SPKGS)) || echo error ignored) ) && ./bootstrap &&  && ./configure --enable-build-as-root ${{ matrix.os.startswith('ubuntu') && '--prefix=/host/sage-${{ matrix.arch }}' || '' }} && MAKE=\"make -j6\" make V=0 $TARGETS_PRE && (echo \"sage_conf @ file://\$(pwd)/pkgs/sage-conf\" && echo \"sage_setup @ file://\$(pwd)/pkgs/sage-setup\") > constraints.txt"
           mkdir -p unpacked
           for pkg in sagemath*objects sagemath*categories sagemath*bliss sagemath*coxeter3 sagemath*mcqd sagemath*meataxe sagemath*sirocco sagemath*tdlib; do
               (cd unpacked && tar xfz - ) < dist/$pkg*.tar.gz