Make FLINT 3.4 the minimum supported version

.github/workflows/buildwheel.yml

@@ -155,14 +155,18 @@ jobs:
           update: true
 
         # Install pkgconfig on Windows from choco rather than from msys and
-        # avoid using the Strawberry one.
+        # put its shim ahead of the Strawberry one on PATH.
       - if: ${{ startsWith( matrix.os , 'windows' ) }}
-        run: choco install -y --stoponfirstfailure --checksum 6004DF17818F5A6DBF19CB335CC92702 pkgconfiglite
+        name: Install pkg-config
+        run: |
+          choco install -y --stoponfirstfailure --checksum 6004DF17818F5A6DBF19CB335CC92702 pkgconfiglite
+          echo "$env:ChocolateyInstall/bin" >> $env:GITHUB_PATH
 
-        # We have to set this here rather than in the cibuildwheel config
-        # This is probably something to do with \ vs / in paths...
       - if: ${{ startsWith( matrix.os , 'windows' ) }}
+        name: Configure pkg-config
         run: |
+          Get-Command pkg-config
+          pkg-config --version
           $pkgConfigPath = "$env:GITHUB_WORKSPACE/.local/lib/pkgconfig"
           $pkgConfigPath = $pkgConfigPath.Replace('\', '/')
           echo "PKG_CONFIG_PATH=$pkgConfigPath" >> $env:GITHUB_ENV
@@ -300,7 +304,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-24.04]
+        os: [ubuntu-26.04]
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
@@ -332,7 +336,7 @@ jobs:
   # Test build with minimum Cython and meson-python versions.
   test_old_build_requires:
     name: 'Test old Cython/meson-python'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
@@ -353,7 +357,7 @@ jobs:
       - run: pip install --no-build-isolation .
       - run: python -m flint.test --verbose
 
-  # For older Ubuntu we have to build Flint >= 3.0.0
+  # Build and test against each supported FLINT release.
   test_flint_releases:
     name: Test flint ${{ matrix.flint-tag }}
     runs-on: ubuntu-22.04
@@ -362,11 +366,9 @@ jobs:
       matrix:
         # Supported Flint versions:
         flint-tag: [
-          'v3.0.1',
-          'v3.2.2',
-          'v3.3.1',
           'v3.4.0',
           'v3.5.0',
+          'v3.6.0',
         ]
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
@@ -416,7 +418,7 @@ jobs:
   # Test that we can make a coverage build and report coverage
   test_coverage_build_setuptools:
     name: Test coverage setuptools build
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
@@ -432,7 +434,7 @@ jobs:
   # Test that we can make a coverage build and report coverage
   test_coverage_build_meson:
     name: Test coverage meson build
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
@@ -448,7 +450,7 @@ jobs:
   # Run SymPy test suite against python-flint master
   test_sympy:
     name: Test SymPy ${{ matrix.sympy-version }}
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     strategy:
       fail-fast: false
       matrix:
@@ -472,7 +474,7 @@ jobs:
   # Run SymPy master branch agains python-flint main
   test_sympy_master:
     name: Test SymPy master
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:

README.md

@@ -37,11 +37,10 @@ Build from source
 -----------------
 
 For other platforms or architectures installation needs to build from source.
-First install FLINT 3. Starting with python-flint 0.5.0 older versions of Flint
-such as 2.9 are not supported any more. Note that as of Flint 3 Arb no longer
-needs to be built separately as it is now merged into Flint.
+First install FLINT 3.4 or newer. Note that as of Flint 3 Arb no longer needs
+to be built separately as it is now merged into Flint.
 
-As of e.g. Ubuntu 24.04 a new enough version of FLINT (at least version 3) can
+As of e.g. Ubuntu 26.04 a new enough version of FLINT (at least version 3.4) can
 be installed from the Ubuntu repos like
 
     sudo apt-get install libflint-dev
@@ -136,15 +135,14 @@ Compatibility table
 -------------------
 
 Generally each release of python-flint will be compatible with a range of
-Python versions. Since python-flint 0.5.0 the minimum supported Flint version
-is `3.0` and each release of python-flint supports all versions of Flint
-`>=3.0` available at the time of release.
+Python and FLINT versions. The supported range for each release is shown
+below.
 
 Compatible versions:
 
 | python-flint | Release date  | CPython     | FLINT      | Cython           |
 |--------------|---------------|-------------|------------|------------------|
-| `0.10.0`     | Not released  | `3.10-3.15` | `3.0-3.6`  | `3.1-3.3`        |
+| `0.10.0`     | Not released  | `3.10-3.15` | `3.4-3.6`  | `3.1-3.3`        |
 | `0.9.0`      |  3rd Jul 2026 | `3.10-3.14` | `3.0-3.6`  | `3.1-3.2`        |
 | `0.8.0`      | 29th Aug 2025 | `3.11-3.14` | `3.0-3.3`  | `3.1` only       |
 | `0.7.0`      | 16th Mar 2025 | `3.11-3.13` | `3.0-3.2`  | `3.0.11-3.1.0a1` |
@@ -174,6 +172,9 @@ Contributors (0.10.0):
 
 Changes (0.10.0):
 
+- [gh-424](https://github.com/flintlib/python-flint/pull/424),
+  Drop support for FLINT versions older than 3.4.0 and remove the associated
+  compatibility code. (OB)
 - [gh-421](https://github.com/flintlib/python-flint/pull/421),
   Add `zpoly` and `zcontent` methods to `fmpq_mpoly`, to get
   the primitive integer polynomial and the `fmpq` content, which