Store hashes in special types so they aren't accidentally encoded as numbers

compiler/rustc_span/src/lib.rs

@@ -59,7 +59,7 @@ pub mod fatal_error;
 
 pub mod profiling;
 
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
+use rustc_data_structures::stable_hasher::{Hash128, Hash64, HashStable, StableHasher};
 use rustc_data_structures::sync::{Lock, Lrc};
 
 use std::borrow::Cow;
@@ -282,22 +282,22 @@ impl RealFileName {
 pub enum FileName {
     Real(RealFileName),
     /// Call to `quote!`.
-    QuoteExpansion(u64),
+    QuoteExpansion(Hash64),
     /// Command line.
-    Anon(u64),
+    Anon(Hash64),
     /// Hack in `src/librustc_ast/parse.rs`.
     // FIXME(jseyfried)
-    MacroExpansion(u64),
-    ProcMacroSourceCode(u64),
+    MacroExpansion(Hash64),
+    ProcMacroSourceCode(Hash64),
     /// Strings provided as `--cfg [cfgspec]` stored in a `crate_cfg`.
-    CfgSpec(u64),
+    CfgSpec(Hash64),
     /// Strings provided as crate attributes in the CLI.
-    CliCrateAttr(u64),
+    CliCrateAttr(Hash64),
     /// Custom sources for explicit parser calls from plugins and drivers.
     Custom(String),
     DocTest(PathBuf, isize),
     /// Post-substitution inline assembly from LLVM.
-    InlineAsm(u64),
+    InlineAsm(Hash64),
 }
 
 impl From<PathBuf> for FileName {
@@ -1343,7 +1343,7 @@ pub struct SourceFile {
     /// Locations of characters removed during normalization.
     pub normalized_pos: Vec<NormalizedPos>,
     /// A hash of the filename, used for speeding up hashing in incremental compilation.
-    pub name_hash: u128,
+    pub name_hash: Hash128,
     /// Indicates which crate this `SourceFile` was imported from.
     pub cnum: CrateNum,
 }
@@ -1472,7 +1472,7 @@ impl<D: Decoder> Decodable<D> for SourceFile {
         };
         let multibyte_chars: Vec<MultiByteChar> = Decodable::decode(d);
         let non_narrow_chars: Vec<NonNarrowChar> = Decodable::decode(d);
-        let name_hash: u128 = Decodable::decode(d);
+        let name_hash = Decodable::decode(d);
         let normalized_pos: Vec<NormalizedPos> = Decodable::decode(d);
         let cnum: CrateNum = Decodable::decode(d);
         SourceFile {
@@ -1514,7 +1514,7 @@ impl SourceFile {
         let name_hash = {
             let mut hasher: StableHasher = StableHasher::new();
             name.hash(&mut hasher);
-            hasher.finish::<u128>()
+            hasher.finish()
         };
         let end_pos = start_pos.to_usize() + src.len();
         assert!(end_pos <= u32::MAX as usize);