diff --git a/runng-sys/tests/tests.rs b/runng-sys/tests/tests.rs
index 0af57928..ea0e376d 100644
--- a/runng-sys/tests/tests.rs
+++ b/runng-sys/tests/tests.rs
@@ -8,7 +8,7 @@ mod tests {
     fn it_works() {
         unsafe {
             let url = CString::new("inproc://test").unwrap();
-            let url = url.as_bytes_with_nul().as_ptr() as *const i8;
+            let url = url.as_bytes_with_nul().as_ptr() as *const std::os::raw::c_char;
 
             // Reply socket
             let mut rep_socket = nng_socket { id: 0 };
diff --git a/runng/src/lib.rs b/runng/src/lib.rs
index 453488c3..2a078382 100644
--- a/runng/src/lib.rs
+++ b/runng/src/lib.rs
@@ -96,8 +96,10 @@ trait InternalSocket {
 }
 
 // Return string and pointer so string isn't dropped
-fn to_cstr(string: &str) -> Result<(std::ffi::CString, *const i8), std::ffi::NulError> {
+fn to_cstr(
+    string: &str,
+) -> Result<(std::ffi::CString, *const std::os::raw::c_char), std::ffi::NulError> {
     let string = std::ffi::CString::new(string)?;
-    let ptr = string.as_bytes_with_nul().as_ptr() as *const i8;
+    let ptr = string.as_bytes_with_nul().as_ptr() as *const std::os::raw::c_char;
     Ok((string, ptr))
 }