fixing windows path

.github/workflows/rust.yml

@@ -33,11 +33,12 @@ jobs:
           mkdir C:\Cbc
           Invoke-WebRequest "https://bintray.com/coin-or/download/download_file?file_path=Cbc-2.9-win32-msvc14.zip" -OutFile "C:\Cbc\Cbc-2.9.zip"
           7z x C:\Cbc\Cbc-2.9.zip -o"C:\Cbc\"
+          Get-ChildItem -Path "C:\Cbc"
+          Get-ChildItem -Path "C:\Cbc\lib"
+          echo "C:\Cbc\lib" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
+          echo $env:GITHUB_PATH
+          type $env:GITHUB_PATH
     - name: Build
-      run: |
-          echo "C:\Cbc\lib" >> $GITHUB_PATH
-          cargo build --verbose --all
+      run: cargo build --verbose --all
     - name: Run tests
-      run: |
-          echo "C:\Cbc\lib" >> $GITHUB_PATH
-          cargo test --verbose --all
+      run: cargo test --verbose --all

coin_cbc_sys/Cargo.toml

@@ -9,3 +9,4 @@ repository = "https://github.com/KardinalAI/coin_cbc"
 keywords = ["MILP", "MIP", "linear programming"]
 categories = ["external-ffi-bindings", "mathematics", "science"]
 license = "MIT "
+build = "build.rs"

coin_cbc_sys/build.rs

@@ -0,0 +1,19 @@
+fn main() {
+    use std::env;
+
+    let is_linux = env::var("CARGO_CFG_UNIX");
+    if is_linux.is_ok() {
+        println!("cargo:rustc-link-lib=CbcSolver");
+        return;
+    }
+
+    let is_win = env::var("CARGO_CFG_WINDOWS");
+    if is_win.is_ok() {
+        println!("cargo:rustc-link-lib=libCbcSolver");
+        let path = env::var("PATH");
+        if let Ok(ok_path) = path {
+            println!("cargo:rustc-link-search={}", ok_path);
+        }
+        return;
+    }
+}

coin_cbc_sys/src/lib.rs

@@ -22,8 +22,6 @@ pub type cbc_callback = Option<
     ),
 >;
 
-#[cfg_attr(unix, link(name = "CbcSolver"))]
-#[cfg_attr(windows, link(name = "libCbcSolver"))]
 extern "C" {
     pub fn Cbc_newModel() -> *mut Cbc_Model;
     pub fn Cbc_deleteModel(model: *mut Cbc_Model);