Auto merge of #47906 - Zoxc:nocycle, r=nikomatsakis

Add a `fatal_cycle` attribute for queries which indicates that they will cause a fatal error on query cycles

This moves us towards the goal of having cycle errors be non-fatal by not relying on the default implementation of `ty::maps::values::Value` which aborts on errors.

r? @nikomatsakis
This commit is contained in:
bors 2018-02-17 02:58:21 +00:00
commit 554fe71ac6
2 changed files with 27 additions and 9 deletions

View file

@ -78,6 +78,11 @@ pub use self::on_disk_cache::OnDiskCache;
// a way that memoizes and does dep-graph tracking,
// wrapping around the actual chain of providers that
// the driver creates (using several `rustc_*` crates).
//
// The result of query must implement Clone. They must also implement ty::maps::values::Value
// which produces an appropiate error value if the query resulted in a query cycle.
// Queries marked with `fatal_cycle` do not need that implementation
// as they will raise an fatal error on query cycles instead.
define_maps! { <'tcx>
/// Records the type of every item.
[] fn type_of: TypeOfItem(DefId) -> Ty<'tcx>,
@ -267,13 +272,13 @@ define_maps! { <'tcx>
[] fn dylib_dependency_formats: DylibDepFormats(CrateNum)
-> Rc<Vec<(CrateNum, LinkagePreference)>>,
[] fn is_panic_runtime: IsPanicRuntime(CrateNum) -> bool,
[] fn is_compiler_builtins: IsCompilerBuiltins(CrateNum) -> bool,
[] fn has_global_allocator: HasGlobalAllocator(CrateNum) -> bool,
[] fn is_sanitizer_runtime: IsSanitizerRuntime(CrateNum) -> bool,
[] fn is_profiler_runtime: IsProfilerRuntime(CrateNum) -> bool,
[] fn panic_strategy: GetPanicStrategy(CrateNum) -> PanicStrategy,
[] fn is_no_builtins: IsNoBuiltins(CrateNum) -> bool,
[fatal_cycle] fn is_panic_runtime: IsPanicRuntime(CrateNum) -> bool,
[fatal_cycle] fn is_compiler_builtins: IsCompilerBuiltins(CrateNum) -> bool,
[fatal_cycle] fn has_global_allocator: HasGlobalAllocator(CrateNum) -> bool,
[fatal_cycle] fn is_sanitizer_runtime: IsSanitizerRuntime(CrateNum) -> bool,
[fatal_cycle] fn is_profiler_runtime: IsProfilerRuntime(CrateNum) -> bool,
[fatal_cycle] fn panic_strategy: GetPanicStrategy(CrateNum) -> PanicStrategy,
[fatal_cycle] fn is_no_builtins: IsNoBuiltins(CrateNum) -> bool,
[] fn extern_crate: ExternCrate(DefId) -> Rc<Option<ExternCrate>>,

View file

@ -183,6 +183,19 @@ macro_rules! profq_key {
}
}
macro_rules! handle_cycle_error {
([][$this: expr]) => {{
Value::from_cycle_error($this.global_tcx())
}};
([fatal_cycle$(, $modifiers:ident)*][$this:expr]) => {{
$this.tcx.sess.abort_if_errors();
unreachable!();
}};
([$other:ident$(, $modifiers:ident)*][$($args:tt)*]) => {
handle_cycle_error!([$($modifiers),*][$($args)*])
};
}
macro_rules! define_maps {
(<$tcx:tt>
$($(#[$attr:meta])*
@ -564,7 +577,7 @@ macro_rules! define_maps {
pub fn $name(self, key: $K) -> $V {
queries::$name::try_get(self.tcx, self.span, key).unwrap_or_else(|mut e| {
e.emit();
Value::from_cycle_error(self.global_tcx())
handle_cycle_error!([$($modifiers)*][self])
})
})*
}
@ -583,7 +596,7 @@ macro_rules! define_maps {
macro_rules! define_map_struct {
(tcx: $tcx:tt,
input: ($(([$(modifiers:tt)*] [$($attr:tt)*] [$name:ident]))*)) => {
input: ($(([$($modifiers:tt)*] [$($attr:tt)*] [$name:ident]))*)) => {
pub struct Maps<$tcx> {
providers: IndexVec<CrateNum, Providers<$tcx>>,
query_stack: RefCell<Vec<(Span, Query<$tcx>)>>,