feat: add clang-18 support with generic version detection

- Add clang-18-libcxx configuration (6 compiler configs total)
- Generic Conan settings patcher: auto-detects Clang version from compiler-id
- Works for any future Clang version without code changes
- Change minimal matrix to use clang-14 instead of clang-17 (faster)
- Sort Conan version list numerically when adding new versions

[ci-nix-full-matrix]

.github/actions/xahau-ga-dependencies/action.yml

@@ -69,6 +69,49 @@ runs:
         conan export external/snappy snappy/1.1.10@xahaud/stable
         conan export external/soci soci/4.0.3@xahaud/stable
 
+    - name: Add Clang version support to Conan if needed
+      if: contains(inputs.compiler-id, 'clang-')
+      shell: bash
+      run: |
+        # Extract Clang version from compiler-id (e.g., "clang-18-libcxx" -> "18")
+        COMPILER_ID="${{ inputs.compiler-id }}"
+        CLANG_VERSION=$(echo "$COMPILER_ID" | sed -n 's/^clang-\([0-9]\+\).*/\1/p')
+        
+        if [ -n "$CLANG_VERSION" ]; then
+          echo "Detected Clang version $CLANG_VERSION from compiler-id"
+          pip install PyYAML
+          python << EOF
+        import yaml
+        from pathlib import Path
+        import os
+        
+        clang_version = os.environ.get('CLANG_VERSION', '')
+        if not clang_version:
+            print("No Clang version detected")
+            exit(0)
+            
+        settings_path = Path.home() / '.conan' / 'settings.yml'
+        with open(settings_path, 'r') as f:
+            settings = yaml.safe_load(f)
+        
+        # Add the detected version to clang versions if not already there
+        clang_versions = settings['compiler']['clang']['version']
+        if clang_version not in clang_versions:
+            clang_versions.append(clang_version)
+            # Sort versions numerically
+            clang_versions.sort(key=lambda x: int(x) if x.isdigit() else float('inf'))
+            
+            with open(settings_path, 'w') as f:
+                yaml.dump(settings, f, default_flow_style=False, sort_keys=False)
+            print(f"Added Clang {clang_version} support to Conan settings")
+        else:
+            print(f"Clang {clang_version} already supported in Conan settings")
+        EOF
+          export CLANG_VERSION
+        else
+          echo "No Clang version found in compiler-id: $COMPILER_ID"
+        fi
+
     - name: Install dependencies
       shell: bash
       run: |

.github/workflows/xahau-ga-nix.yml

@@ -24,7 +24,7 @@ jobs:
           import json
           import os
           
-          # Full matrix with all 5 compiler configurations
+          # Full matrix with all 6 compiler configurations
           # Each configuration includes all parameters needed by the build job
           full_matrix = [
               {
@@ -73,13 +73,24 @@ jobs:
                   "compiler_version": 17,
                   "stdlib": "libcxx",
                   "configuration": "Debug"
+              },
+              {
+                  # Clang 18 - testing if it's faster than Clang 17 with libc++
+                  # Requires patching Conan v1 settings.yml to add version 18
+                  "compiler_id": "clang-18-libcxx",
+                  "compiler": "clang",
+                  "cc": "clang-18",
+                  "cxx": "clang++-18",
+                  "compiler_version": 18,
+                  "stdlib": "libcxx",
+                  "configuration": "Debug"
               }
           ]
           
-          # Minimal matrix for PRs and feature branches (newest gcc + newest clang)
+          # Minimal matrix for PRs and feature branches
           minimal_matrix = [
-              full_matrix[1],  # gcc-13
-              full_matrix[4]   # clang-17
+              full_matrix[1],  # gcc-13 (middle-ground gcc)
+              full_matrix[2]   # clang-14 (mature, stable clang)
           ]
           
           # Determine which matrix to use based on the target branch
@@ -111,9 +122,9 @@ jobs:
           # Select the appropriate matrix
           if use_full:
               if force_full:
-                  print(f"Using FULL matrix (5 configs) - forced by [ci-nix-full-matrix] tag")
+                  print(f"Using FULL matrix (6 configs) - forced by [ci-nix-full-matrix] tag")
               else:
-                  print(f"Using FULL matrix (5 configs) - targeting main branch")
+                  print(f"Using FULL matrix (6 configs) - targeting main branch")
               matrix = full_matrix
           else:
               print(f"Using MINIMAL matrix (2 configs) - feature branch/PR")