From fcc6be2b01fd0b88c1d0449162e17b44b4d1d7c7 Mon Sep 17 00:00:00 2001
From: Maximilian Hristache <mhristache@gmail.com>
Date: Sat, 28 Nov 2015 16:24:08 +0100
Subject: [PATCH] Avoid empty include paths (i.e. cc -I "" ) as they are not
 supported by GCC. Fix #311

---
 openssl-sys/build.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/openssl-sys/build.rs b/openssl-sys/build.rs
index d8399c54..0e3a76d2 100644
--- a/openssl-sys/build.rs
+++ b/openssl-sys/build.rs
@@ -15,8 +15,11 @@ fn main() {
         // rustc doesn't seem to work with pkg-config's output in mingw64
         if !target.contains("windows") {
             if let Ok(info) = pkg_config::find_library("openssl") {
-                let paths = env::join_paths(info.include_paths).unwrap();
-                println!("cargo:include={}", paths.to_str().unwrap());
+                // avoid empty include paths as they are not supported by GCC
+                if info.include_paths.len() > 0 {
+                    let paths = env::join_paths(info.include_paths).unwrap();
+                    println!("cargo:include={}", paths.to_str().unwrap());
+                }
                 return;
             }
         }