Auto merge of #122 - myfreeweb:master, r=jdm

Fix build on FreeBSD

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Author: bors-servo

build.rs

@@ -42,17 +42,17 @@ fn main() {
         .expect("Failed to run `make`");
     assert!(result.success());
     println!("cargo:rustc-link-search=native={}/js/src", out_dir);
+    println!("cargo:rustc-link-lib=static=js_static"); // Must come before c++
     if target.contains("windows") {
         println!("cargo:rustc-link-lib=winmm");
         println!("cargo:rustc-link-lib=psapi");
         if target.contains("gnu") {
             println!("cargo:rustc-link-lib=stdc++");
         }
-    } else if target.contains("apple") {
+    } else if target.contains("apple") || target.contains("freebsd") {
         println!("cargo:rustc-link-lib=c++");
     } else {
         println!("cargo:rustc-link-lib=stdc++");
     }
-    println!("cargo:rustc-link-lib=static=js_static");
     println!("cargo:outdir={}", out_dir);
 }

makefile.cargo

@@ -39,9 +39,16 @@ CONFIGURE_FLAGS += --target=$(TARGET) --disable-gold
 else
 
 ifeq (,$(VCINSTALLDIR))
-CC ?= gcc
-CPP ?= gcc -E
-CXX ?= g++
+	ifeq (freebsd,$(findstring freebsd,$(TARGET)))
+		# Does not symlink clang as "gcc" like macOS does
+		CC ?= clang
+		CPP ?= clang -E
+		CXX ?= clang++
+	else
+		CC ?= gcc
+		CPP ?= gcc -E
+		CXX ?= g++
+	endif
 AR ?= ar
 PYTHON ?= python
 endif