Get rid of env var race condition once and for all

4 files changed, 63 insertions, 38 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 9e41c301087..00ae333b467 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -21,24 +21,24 @@ dependencies = [
 [[package]]
 name = "backtrace"
 version = "0.3.2"
-source = "git+https://github.com/alexcrichton/backtrace-rs#3d96a9242ed2096984d15d177f4762b699bee6d4"
+source = "git+https://github.com/alexcrichton/backtrace-rs#ac8f8d150ad114b735a020c37762426fc7ad18c4"
 dependencies = [
  "backtrace-sys 0.1.12 (git+https://github.com/alexcrichton/backtrace-rs)",
  "cfg-if 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "dbghelp-sys 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.28 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-demangle 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.30 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-demangle 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "backtrace-sys"
 version = "0.1.12"
-source = "git+https://github.com/alexcrichton/backtrace-rs#3d96a9242ed2096984d15d177f4762b699bee6d4"
+source = "git+https://github.com/alexcrichton/backtrace-rs#ac8f8d150ad114b735a020c37762426fc7ad18c4"
 dependencies = [
- "gcc 0.3.51 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gcc 0.3.53 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.30 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -99,7 +99,7 @@ dependencies = [
 
 [[package]]
 name = "dtoa"
-version = "0.4.1"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -113,12 +113,12 @@ dependencies = [
 
 [[package]]
 name = "gcc"
-version = "0.3.51"
+version = "0.3.53"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "itoa"
-version = "0.3.1"
+version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -137,7 +137,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "libc"
-version = "0.2.28"
+version = "0.2.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -175,7 +175,7 @@ name = "memchr"
 version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.30 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -207,7 +207,7 @@ name = "rand"
 version = "0.3.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "magenta 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -230,7 +230,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "rustc-demangle"
-version = "0.1.4"
+version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -267,8 +267,8 @@ name = "serde_json"
 version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "dtoa 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "itoa 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "dtoa 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "itoa 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.1.40 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -353,13 +353,13 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum conv 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "78ff10625fd0ac447827aa30ea8b861fead473bb60aeb73af6c1c58caf0d1299"
 "checksum custom_derive 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "ef8ae57c4978a2acd8b869ce6b9ca1dfe817bff704c220209fdef2c0b75a01b9"
 "checksum dbghelp-sys 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "97590ba53bcb8ac28279161ca943a924d1fd4a8fb3fa63302591647c4fc5b850"
-"checksum dtoa 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "80c8b71fd71146990a9742fc06dcbbde19161a267e0ad4e572c35162f4578c90"
+"checksum dtoa 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "09c3753c3db574d215cba4ea76018483895d7bff25a31b49ba45db21c48e50ab"
 "checksum env_logger 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3ddf21e73e016298f5cb37d6ef8e8da8e39f91f9ec8b0df44b7deb16a9f8cd5b"
-"checksum gcc 0.3.51 (registry+https://github.com/rust-lang/crates.io-index)" = "120d07f202dcc3f72859422563522b66fe6463a4c513df062874daad05f85f0a"
-"checksum itoa 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "eb2f404fbc66fd9aac13e998248505e7ecb2ad8e44ab6388684c5fb11c6c251c"
+"checksum gcc 0.3.53 (registry+https://github.com/rust-lang/crates.io-index)" = "e8310f7e9c890398b0e80e301c4f474e9918d2b27fca8f48486ca775fa9ffc5a"
+"checksum itoa 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f74cf6ca1bdbc28496a2b9798ab7fccc2ca5a42cace95bb2b219577216a5fb90"
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
 "checksum lazy_static 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "3b37545ab726dd833ec6420aaba8231c5b320814b9029ad585555d2a03e94fbf"
-"checksum libc 0.2.28 (registry+https://github.com/rust-lang/crates.io-index)" = "bb7b49972ee23d8aa1026c365a5b440ba08e35075f18c459980c7395c221ec48"
+"checksum libc 0.2.30 (registry+https://github.com/rust-lang/crates.io-index)" = "2370ca07ec338939e356443dac2296f581453c35fe1e3a3ed06023c49435f915"
 "checksum log 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)" = "880f77541efa6e5cc74e76910c9884d9859683118839d6a1dc3b11e63512565b"
 "checksum log_settings 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3d382732ea0fbc09790c4899db3255bdea0fc78b54bf234bd18a63bb603915b6"
 "checksum magenta 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4bf0336886480e671965f794bc9b6fce88503563013d1bfb7a502c81fe3ac527"
@@ -370,7 +370,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum rand 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)" = "eb250fd207a4729c976794d03db689c9be1d634ab5a1c9da9492a13d8fecbcdf"
 "checksum regex 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1731164734096285ec2a5ec7fea5248ae2f5485b3feeb0115af4fda2183b2d1b"
 "checksum regex-syntax 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ad890a5eef7953f55427c50575c680c42841653abd2b028b68cd223d157f62db"
-"checksum rustc-demangle 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "3058a43ada2c2d0b92b3ae38007a2d0fa5e9db971be260e0171408a4ff471c95"
+"checksum rustc-demangle 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "aee45432acc62f7b9a108cc054142dac51f979e69e71ddce7d6fc7adf29e817e"
 "checksum rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)" = "dcf128d1287d2ea9d80910b5f1120d0b8eede3fbf1abe91c40d39ea7d51e6fda"
 "checksum serde 1.0.11 (registry+https://github.com/rust-lang/crates.io-index)" = "f7726f29ddf9731b17ff113c461e362c381d9d69433f79de4f3dd572488823e9"
 "checksum serde_derive 1.0.11 (registry+https://github.com/rust-lang/crates.io-index)" = "cf823e706be268e73e7747b147aa31c8f633ab4ba31f115efb57e5047c3a76dd"
diff --git a/miri/bin/miri.rs b/miri/bin/miri.rs
index 29c47e35570..337a723a40d 100644
--- a/miri/bin/miri.rs
+++ b/miri/bin/miri.rs
@@ -19,7 +19,11 @@ use rustc::ty::TyCtxt;
 use syntax::ast::{self, MetaItemKind, NestedMetaItemKind};
 use std::path::PathBuf;
 
-struct MiriCompilerCalls(RustcDefaultCalls);
+struct MiriCompilerCalls {
+    default: RustcDefaultCalls,
+    /// whether we are building for the host
+    host_target: bool,
+}
 
 impl<'a> CompilerCalls<'a> for MiriCompilerCalls {
     fn early_callback(
@@ -30,7 +34,7 @@ impl<'a> CompilerCalls<'a> for MiriCompilerCalls {
         descriptions: &rustc_errors::registry::Registry,
         output: ErrorOutputType,
     ) -> Compilation {
-        self.0.early_callback(
+        self.default.early_callback(
             matches,
             sopts,
             cfg,
@@ -47,7 +51,7 @@ impl<'a> CompilerCalls<'a> for MiriCompilerCalls {
         ofile: &Option<PathBuf>,
         descriptions: &rustc_errors::registry::Registry,
     ) -> Option<(Input, Option<PathBuf>)> {
-        self.0.no_input(
+        self.default.no_input(
             matches,
             sopts,
             cfg,
@@ -64,17 +68,17 @@ impl<'a> CompilerCalls<'a> for MiriCompilerCalls {
         odir: &Option<PathBuf>,
         ofile: &Option<PathBuf>,
     ) -> Compilation {
-        self.0.late_callback(matches, sess, input, odir, ofile)
+        self.default.late_callback(matches, sess, input, odir, ofile)
     }
     fn build_controller(
         &mut self,
         sess: &Session,
         matches: &getopts::Matches,
     ) -> CompileController<'a> {
-        let mut control = self.0.build_controller(sess, matches);
+        let mut control = self.default.build_controller(sess, matches);
         control.after_hir_lowering.callback = Box::new(after_hir_lowering);
         control.after_analysis.callback = Box::new(after_analysis);
-        if std::env::var("MIRI_HOST_TARGET") != Ok("yes".to_owned()) {
+        if !self.host_target {
             // only fully compile targets on the host
             control.after_analysis.stop = Compilation::Stop;
         }
@@ -254,6 +258,16 @@ fn main() {
 
     // for auxilary builds in unit tests
     args.push("-Zalways-encode-mir".to_owned());
+    let mut host_target = false;
+    args.retain(|arg| if arg == "--miri_host_target" {
+        host_target = true;
+        false // remove the flag, rustc doesn't know it
+    } else {
+        true
+    });
 
-    rustc_driver::run_compiler(&args, &mut MiriCompilerCalls(RustcDefaultCalls), None, None);
+    rustc_driver::run_compiler(&args, &mut MiriCompilerCalls {
+        default: RustcDefaultCalls,
+        host_target,
+    }, None, None);
 }
diff --git a/rustc_tests/src/main.rs b/rustc_tests/src/main.rs
index 4cff381b332..a44880f1125 100644
--- a/rustc_tests/src/main.rs
+++ b/rustc_tests/src/main.rs
@@ -20,7 +20,11 @@ use rustc::hir::{self, itemlikevisit};
 use rustc::ty::TyCtxt;
 use syntax::ast;
 
-struct MiriCompilerCalls(RustcDefaultCalls);
+struct MiriCompilerCalls {
+    default: RustcDefaultCalls,
+    /// whether we are building for the host
+    host_target: bool,
+}
 
 impl<'a> CompilerCalls<'a> for MiriCompilerCalls {
     fn early_callback(
@@ -31,7 +35,7 @@ impl<'a> CompilerCalls<'a> for MiriCompilerCalls {
         descriptions: &rustc_errors::registry::Registry,
         output: ErrorOutputType
     ) -> Compilation {
-        self.0.early_callback(matches, sopts, cfg, descriptions, output)
+        self.default.early_callback(matches, sopts, cfg, descriptions, output)
     }
     fn no_input(
         &mut self,
@@ -42,7 +46,7 @@ impl<'a> CompilerCalls<'a> for MiriCompilerCalls {
         ofile: &Option<PathBuf>,
         descriptions: &rustc_errors::registry::Registry
     ) -> Option<(Input, Option<PathBuf>)> {
-        self.0.no_input(matches, sopts, cfg, odir, ofile, descriptions)
+        self.default.no_input(matches, sopts, cfg, odir, ofile, descriptions)
     }
     fn late_callback(
         &mut self,
@@ -52,13 +56,13 @@ impl<'a> CompilerCalls<'a> for MiriCompilerCalls {
         odir: &Option<PathBuf>,
         ofile: &Option<PathBuf>
     ) -> Compilation {
-        self.0.late_callback(matches, sess, input, odir, ofile)
+        self.default.late_callback(matches, sess, input, odir, ofile)
     }
     fn build_controller(&mut self, sess: &Session, matches: &getopts::Matches) -> CompileController<'a> {
-        let mut control = self.0.build_controller(sess, matches);
+        let mut control = self.default.build_controller(sess, matches);
         control.after_hir_lowering.callback = Box::new(after_hir_lowering);
         control.after_analysis.callback = Box::new(after_analysis);
-        if std::env::var("MIRI_HOST_TARGET") != Ok("yes".to_owned()) {
+        if !self.host_target {
             // only fully compile targets on the host
             control.after_analysis.stop = Compilation::Stop;
         }
@@ -139,7 +143,15 @@ fn main() {
         }
         let stderr = std::io::stderr();
         write!(stderr.lock(), "test [miri-pass] {} ... ", path.display()).unwrap();
-        let mut args: Vec<String> = std::env::args().collect();
+        let mut host_target = false;
+        let mut args: Vec<String> = std::env::args().filter(|arg| {
+            if arg == "--miri_host_target" {
+                host_target = true;
+                false // remove the flag, rustc doesn't know it
+            } else {
+                true
+            }
+        }).collect();
         // file to process
         args.push(path.display().to_string());
 
diff --git a/tests/compiletest.rs b/tests/compiletest.rs
index 7a220ec7627..e7c82367b29 100644
--- a/tests/compiletest.rs
+++ b/tests/compiletest.rs
@@ -126,15 +126,14 @@ fn miri_pass(path: &str, target: &str, host: &str, fullmir: bool, opt: bool) {
         // For now, only validate without optimizations.  Inlining breaks validation.
         flags.push("-Zmir-emit-validate=1".to_owned());
     }
+    if target == host {
+        flags.push("--miri_host_target".to_owned());
+    }
     config.target_rustcflags = Some(flags.join(" "));
     // don't actually execute the final binary, it might be for other targets and we only care
     // about running miri, not the binary.
     config.runtool = Some("echo \"\" || ".to_owned());
-    if target == host {
-        std::env::set_var("MIRI_HOST_TARGET", "yes");
-    }
     compiletest::run_tests(&config);
-    std::env::set_var("MIRI_HOST_TARGET", "");
 }
 
 fn is_target_dir<P: Into<PathBuf>>(path: P) -> bool {