Misc tweaks

Author: Zoxc

config.toml.example

@@ -346,6 +346,9 @@
 # Whether to deny warnings in crates
 #deny-warnings = true
 
+# Print backtrace on internal compiler errors during bootstrap
+#backtrace-on-ice = false
+
 # =============================================================================
 # Options for specific targets
 #

src/Cargo.lock

@@ -107,6 +107,13 @@ fn main() {
              env::join_paths(&dylib_path).unwrap());
     let mut maybe_crate = None;
 
+    // Print backtrace in case of ICE
+    if env::var("RUSTC_BACKTRACE_ON_ICE").is_ok() && env::var("RUST_BACKTRACE").is_err() {
+        cmd.env("RUST_BACKTRACE", "1");
+    }
+
+    cmd.env("RUSTC_BREAK_ON_ICE", "1");
+
     if let Some(target) = target {
         // The stage0 compiler has a special sysroot distinct from what we
         // actually downloaded, so we just always pass the `--sysroot` option.

src/bootstrap/bin/rustc.rs

@@ -706,6 +706,10 @@ impl<'a> Builder<'a> {
             cargo.env("RUSTC_PRINT_STEP_TIMINGS", "1");
         }
 
+        if self.config.backtrace_on_ice {
+            cargo.env("RUSTC_BACKTRACE_ON_ICE", "1");
+        }
+
         cargo.env("RUSTC_VERBOSE", format!("{}", self.verbosity));
 
         // in std, we want to avoid denying warnings for stage 0 as that makes cfg's painful.

src/bootstrap/builder.rs

@@ -72,6 +72,7 @@ pub struct Config {
     pub dry_run: bool,
 
     pub deny_warnings: bool,
+    pub backtrace_on_ice: bool,
 
     // llvm codegen options
     pub llvm_enabled: bool,
@@ -306,6 +307,7 @@ struct Rust {
     wasm_syscall: Option<bool>,
     lld: Option<bool>,
     deny_warnings: Option<bool>,
+    backtrace_on_ice: Option<bool>,
 }
 
 /// TOML representation of how each build target is configured.
@@ -531,6 +533,7 @@ impl Config {
             config.musl_root = rust.musl_root.clone().map(PathBuf::from);
             config.save_toolstates = rust.save_toolstates.clone().map(PathBuf::from);
             set(&mut config.deny_warnings, rust.deny_warnings.or(flags.warnings));
+            set(&mut config.backtrace_on_ice, rust.backtrace_on_ice);
 
             if let Some(ref backends) = rust.codegen_backends {
                 config.rust_codegen_backends = backends.iter()

src/bootstrap/config.rs

@@ -122,12 +122,10 @@ struct JOBOBJECT_BASIC_LIMIT_INFORMATION {
 }
 
 pub unsafe fn setup(build: &mut Build) {
-    // Tell Windows to not show any UI on errors (such as not finding a required dll
-    // during startup or terminating abnormally).  This is important for running tests,
-    // since some of them use abnormal termination by design.
-    // This mode is inherited by all child processes.
-    let mode = SetErrorMode(SEM_NOGPFAULTERRORBOX); // read inherited flags
-    SetErrorMode(mode | SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX);
+    // Enable the Windows Error Reporting dialog which msys disables,
+    // so we can JIT debug rustc
+    let mode = SetErrorMode(0);
+    SetErrorMode(mode & !SEM_NOGPFAULTERRORBOX);
 
     // Create a new job object for us to use
     let job = CreateJobObjectW(0 as *mut _, 0 as *const _);

src/bootstrap/job.rs

@@ -58,6 +58,17 @@ fn panic_hook(info: &panic::PanicInfo) {
         if backtrace {
             TyCtxt::try_print_query_stack();
         }
+
+        #[cfg(windows)]
+        unsafe {
+            if env::var("RUSTC_BREAK_ON_ICE").is_ok() {
+                extern "system" {
+                    fn DebugBreak();
+                }
+                // Trigger a debugger if we crashed during bootstrap
+                DebugBreak();
+            }
+        }
     }
 }
 

src/librustc/util/common.rs

@@ -65,7 +65,6 @@
        html_root_url = "https://doc.rust-lang.org/nightly/")]
 
 #![feature(rustc_diagnostic_macros)]
-#![feature(staged_api)]
 
 #[macro_use] extern crate syntax;
 

src/librustc_plugin/lib.rs

@@ -128,8 +128,6 @@ impl<'a> Registry<'a> {
     /// This can be used in place of `register_syntax_extension` to register legacy custom derives
     /// (i.e. attribute syntax extensions whose name begins with `derive_`). Legacy custom
     /// derives defined by this function do not trigger deprecation warnings when used.
-    #[unstable(feature = "rustc_private", issue = "27812")]
-    #[rustc_deprecated(since = "1.15.0", reason = "replaced by macros 1.1 (RFC 1861)")]
     pub fn register_custom_derive(&mut self, name: ast::Name, extension: SyntaxExtension) {
         assert!(name.as_str().starts_with("derive_"));
         self.whitelisted_custom_derives.push(name);

src/librustc_plugin/registry.rs

@@ -19,5 +19,6 @@ rustfix = "0.2"
 libc = "0.2"
 
 [target.'cfg(windows)'.dependencies]
+lazy_static = "1.0"
 miow = "0.3"
 winapi = { version = "0.3", features = ["winerror"] }