Try to evaluate constants in legacy mangling

Author: oli-obk

compiler/rustc_symbol_mangling/src/legacy.rs

@@ -8,6 +8,7 @@ use rustc_middle::bug;
 use rustc_middle::ty::print::{PrettyPrinter, Print, PrintError, Printer};
 use rustc_middle::ty::{
     self, GenericArg, GenericArgKind, Instance, ReifyReason, Ty, TyCtxt, TypeVisitableExt,
+    TypingEnv,
 };
 use tracing::debug;
 
@@ -239,6 +240,8 @@ impl<'tcx> Printer<'tcx> for SymbolPrinter<'tcx> {
                 self.write_str("[")?;
                 self.print_type(ty)?;
                 self.write_str("; ")?;
+                let size =
+                    self.tcx.normalize_erasing_regions(TypingEnv::fully_monomorphized(), size);
                 if let Some(size) = size.try_to_target_usize(self.tcx()) {
                     write!(self, "{size}")?
                 } else if let ty::ConstKind::Param(param) = size.kind() {
@@ -272,6 +275,7 @@ impl<'tcx> Printer<'tcx> for SymbolPrinter<'tcx> {
     }
 
     fn print_const(&mut self, ct: ty::Const<'tcx>) -> Result<(), PrintError> {
+        let ct = self.tcx.normalize_erasing_regions(TypingEnv::fully_monomorphized(), ct);
         // only print integers
         match ct.kind() {
             ty::ConstKind::Value(ty, ty::ValTree::Leaf(scalar)) if ty.is_integral() => {

tests/ui/symbol-names/types.legacy.stderr

@@ -502,19 +502,19 @@ error: demangling-alt(a::b::Type<[T; N]>)
 LL |     #[rustc_symbol_name]
    |     ^^^^^^^^^^^^^^^^^^^^
 
-error: symbol-name(_ZN1a1b35Type$LT$$u5b$u8$u3b$$u20$_$u5d$$GT$17h[HASH]E)
+error: symbol-name(_ZN1a1b35Type$LT$$u5b$u8$u3b$$u20$0$u5d$$GT$17h[HASH]E)
   --> $DIR/types.rs:272:5
    |
 LL |     #[rustc_symbol_name]
    |     ^^^^^^^^^^^^^^^^^^^^
 
-error: demangling(a::b::Type<[u8; _]>::h[HASH])
+error: demangling(a::b::Type<[u8; 0]>::h[HASH])
   --> $DIR/types.rs:272:5
    |
 LL |     #[rustc_symbol_name]
    |     ^^^^^^^^^^^^^^^^^^^^
 
-error: demangling-alt(a::b::Type<[u8; _]>)
+error: demangling-alt(a::b::Type<[u8; 0]>)
   --> $DIR/types.rs:272:5
    |
 LL |     #[rustc_symbol_name]

tests/ui/symbol-names/types.rs

@@ -270,9 +270,9 @@ pub fn b() {
     const ZERO: usize = 0;
 
     #[rustc_symbol_name]
-    //[legacy,verbose-legacy]~^ ERROR symbol-name(_ZN1a1b35Type$LT$$u5b$u8$u3b$$u20$_$u5d$$GT$
-    //[legacy,verbose-legacy]~| ERROR demangling(a::b::Type<[u8; _]>::
-    //[legacy,verbose-legacy]~| ERROR demangling-alt(a::b::Type<[u8; _]>)
+    //[legacy,verbose-legacy]~^ ERROR symbol-name(_ZN1a1b35Type$LT$$u5b$u8$u3b$$u20$0$u5d$$GT$
+    //[legacy,verbose-legacy]~| ERROR demangling(a::b::Type<[u8; 0]>::
+    //[legacy,verbose-legacy]~| ERROR demangling-alt(a::b::Type<[u8; 0]>)
     //[v0]~^^^^ ERROR symbol-name(_RMsq_NvCsCRATE_HASH_1a1bINtB<REF>_4TypeAhj0_E)
     //[v0]~| ERROR ::b::Type<[u8; 0usize]>>)
     //[v0]~| ERROR demangling-alt(<a::b::Type<[u8; 0]>>)

tests/ui/symbol-names/types.verbose-legacy.stderr

@@ -502,19 +502,19 @@ error: demangling-alt(a::b::Type<[T; N]>)
 LL |     #[rustc_symbol_name]
    |     ^^^^^^^^^^^^^^^^^^^^
 
-error: symbol-name(_ZN1a1b35Type$LT$$u5b$u8$u3b$$u20$_$u5d$$GT$17h[HASH]E)
+error: symbol-name(_ZN1a1b35Type$LT$$u5b$u8$u3b$$u20$0$u5d$$GT$17h[HASH]E)
   --> $DIR/types.rs:272:5
    |
 LL |     #[rustc_symbol_name]
    |     ^^^^^^^^^^^^^^^^^^^^
 
-error: demangling(a::b::Type<[u8; _]>::h[HASH])
+error: demangling(a::b::Type<[u8; 0]>::h[HASH])
   --> $DIR/types.rs:272:5
    |
 LL |     #[rustc_symbol_name]
    |     ^^^^^^^^^^^^^^^^^^^^
 
-error: demangling-alt(a::b::Type<[u8; _]>)
+error: demangling-alt(a::b::Type<[u8; 0]>)
   --> $DIR/types.rs:272:5
    |
 LL |     #[rustc_symbol_name]