Use a custom env variable to get the clang flags

build.rs

@@ -6,8 +6,8 @@ extern crate bindgen;
 extern crate cc;
 
 use std::env;
-use std::path::PathBuf;
 use std::ffi::{OsStr, OsString};
+use std::path::PathBuf;
 use std::process::{Command, Stdio};
 
 fn main() {
@@ -33,24 +33,14 @@ fn find_make() -> OsString {
 }
 
 fn cc_flags() -> Vec<&'static str> {
-    let mut result = vec![
-        "-DRUST_BINDGEN",
-        "-DSTATIC_JS_API",
-    ];
+    let mut result = vec!["-DRUST_BINDGEN", "-DSTATIC_JS_API"];
 
     if cfg!(feature = "debugmozjs") {
-        result.extend(&[
-            "-DJS_GC_ZEAL",
-            "-DDEBUG",
-            "-DJS_DEBUG",
-        ]);
+        result.extend(&["-DJS_GC_ZEAL", "-DDEBUG", "-DJS_DEBUG"]);
     }
 
     if cfg!(windows) {
-        result.extend(&[
-            "-std=c++14",
-            "-DWIN32",
-        ]);
+        result.extend(&["-std=c++14", "-DWIN32"]);
     } else {
         result.extend(&[
             "-std=gnu++11",
@@ -88,7 +78,8 @@ fn build_jsapi() {
         cmd.env("MAKEFLAGS", makeflags);
     }
 
-    let result = cmd.args(&["-R", "-f", "makefile.cargo"])
+    let result = cmd
+        .args(&["-R", "-f", "makefile.cargo"])
         .stdout(Stdio::inherit())
         .stderr(Stdio::inherit())
         .status()
@@ -111,10 +102,9 @@ fn build_jsapi() {
     println!("cargo:outdir={}", out_dir);
 }
 
-
 fn build_jsglue() {
     let out = PathBuf::from(env::var("OUT_DIR").unwrap());
-        
+
     let mut build = cc::Build::new();
     build.cpp(true);
 
@@ -142,7 +132,7 @@ fn build_jsapi_bindings() {
     config.constructors = false;
     config.destructors = false;
     config.methods = false;
-    
+
     let mut builder = bindgen::builder()
         .rust_target(bindgen::RustTarget::Stable_1_19)
         .header("./src/jsglue.hpp")
@@ -159,7 +149,7 @@ fn build_jsapi_bindings() {
         builder = builder.clang_arg("-fms-compatibility");
     }
 
-    if let Ok(flags) = env::var("CXXFLAGS") {
+    if let Ok(flags) = env::var("BINDGEN_CXXFLAGS") {
         for flag in flags.split_whitespace() {
             builder = builder.clang_arg(flag);
         }
@@ -199,10 +189,12 @@ fn build_jsapi_bindings() {
         builder = builder.module_raw_line(module, raw_line);
     }
 
-    let bindings = builder.generate()
-        .expect("Should generate JSAPI bindings OK");
+    let bindings = builder
+        .generate()
+        .expect("Should generate JSAPI bindings OK.");
 
-    bindings.write_to_file(out.join("jsapi.rs"))
+    bindings
+        .write_to_file(out.join("jsapi.rs"))
         .expect("Should write bindings to file OK");
 
     println!("cargo:rerun-if-changed=src/jsglue.hpp");
@@ -219,11 +211,7 @@ const UNSAFE_IMPL_SYNC_TYPES: &'static [&'static str] = &[
 
 /// Types which we want to generate bindings for (and every other type they
 /// transitively use).
-const WHITELIST_TYPES: &'static [&'static str] = &[
-    "JS.*",
-    "js::.*",
-    "mozilla::.*",
-];
+const WHITELIST_TYPES: &'static [&'static str] = &["JS.*", "js::.*", "mozilla::.*"];
 
 /// Global variables we want to generate bindings to.
 const WHITELIST_VARS: &'static [&'static str] = &[
@@ -240,7 +228,7 @@ const WHITELIST_VARS: &'static [&'static str] = &[
 
 /// Functions we want to generate bindings to.
 const WHITELIST_FUNCTIONS: &'static [&'static str] = &[
-   "ExceptionStackOrNull",
+    "ExceptionStackOrNull",
     "glue::.*",
     "JS::.*",
     "js::.*",
@@ -287,5 +275,8 @@ const MODULE_RAW_LINES: &'static [(&'static str, &'static str)] = &[
     ("root", "pub type FILE = ::libc::FILE;"),
     ("root", "pub type JSJitInfo = ::jsjit::JSJitInfo;"),
     ("root::JS", "pub type Heap<T> = ::jsgc::Heap<T>;"),
-    ("root::JS", "pub type AutoGCRooterTag = AutoGCRooter__bindgen_ty_1;"),
+    (
+        "root::JS",
+        "pub type AutoGCRooterTag = AutoGCRooter__bindgen_ty_1;",
+    ),
 ];