fixup! Attempt supporting spaces in CC path

jemalloc-sys/build.rs

@@ -75,16 +75,30 @@ fn expect_env(name: &str) -> String {
 
 /// Attempts to turn the given path into a short path. Returns none in case of
 /// error.
-fn to_short_path(path: &Path) -> Option<PathBuf> {
-    let path = match Command::new("cmd").args(&["/c", "@echo %~s1"]).arg(path).output() {
+fn to_short_path(orig_path: &Path) -> Option<PathBuf> {
+    let path = match Command::new("cmd").args(["/c", "@echo %~s1"]).arg(orig_path).output() {
         Ok(v) if v.status.success() => v.stdout,
-        Ok(v) => warn!("Failed to expand {} to a short path, the command exited with status {}", compiler_path.display(), v.status),
-        Err(err) => warn!("Failed to expand {} to a short path: {}", compiler_path.display(), err),
+        Ok(v) => {
+            warning!("Failed to expand {} to a short path, the command exited with status {}", orig_path.display(), v.status);
+            return None;
+        }
+        Err(err) => {
+            warning!("Failed to expand {} to a short path: {}", orig_path.display(), err);
+            return None;
+        }
     };
 
     // TODO: Turn the Vec<u8> into an OsString so we can lossly turn it into a
     // PathBuf.
-    PathBuf::from(String::from_utf8(path))
+    let path = match String::from_utf8(path) {
+        Ok(v) => v,
+        Err(_err) => {
+            warning!("Short path of {} is not valid utf-8", orig_path.display());
+            return None;
+        }
+    };
+
+    Some(PathBuf::from(path))
 }
 
 // TODO: split main functions and remove following allow.
@@ -168,15 +182,15 @@ fn main() {
         .map(|s| s.to_str().unwrap())
         .collect::<Vec<_>>()
         .join(" ");
-    let mut compiler_path = compiler.path();
+    let mut compiler_path = compiler.path().to_owned();
     if cfg!(windows) && compiler_path.to_string_lossy().contains(' ') {
         // Autoconf does not support spaces in the compiler path. This is not
         // usually a problem, except on windows where the MSVC compiler (cl.exe)
         // is usually found in C:\Program Files, which has a space. Fortunately,
         // windows has a trick that can be used: the path can be turned into a
         // "short path", turning C:\Program Files into C:\PROGRA~2. Through this
         // trick, we can attempt to eliminate the spaces.
-        if let Some(short_path) = to_short_path(compiler_path) {
+        if let Some(short_path) = to_short_path(&compiler_path) {
             compiler_path = short_path;
         }
     }