update workflow

Author: thomas-risse

.github/workflows/c-cpp.yml

@@ -113,11 +113,19 @@ jobs:
       uses: actions/checkout@v4
     - name: Install submodules
       run: git submodule update --init --recursive
-    - name: Install Eigen3
-      uses: kupns-aka-kupa/setup-eigen3@v1
     - name: Build external
       run: |
         bash
+        mkdir eigen
+        cd eigen
+        curl -L -O https://gitlab.com/libeigen/eigen/-/archive/3.4.0/eigen-3.4.0.zip
+        unzip eigen-3.4.0.zip
+        cd eigen-3.4.0
+        mkdir build
+        cd build
+        cmake ..
+        make install
+        cd ../../../
         cd src/maxmsp
         mkdir -p ./1dSAV/build
         cd ./1dSAV/build