From 4173e971b8c06d00b5bf9fb0133220cb37cf99da Mon Sep 17 00:00:00 2001 From: Ralf Jung Date: Sun, 7 Aug 2022 10:36:42 -0400 Subject: remove an ineffective check in const_prop --- compiler/rustc_const_eval/src/interpret/place.rs | 2 +- compiler/rustc_const_eval/src/interpret/projection.rs | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) (limited to 'compiler/rustc_const_eval/src') diff --git a/compiler/rustc_const_eval/src/interpret/place.rs b/compiler/rustc_const_eval/src/interpret/place.rs index 7aa76fe1dae..d56323448ce 100644 --- a/compiler/rustc_const_eval/src/interpret/place.rs +++ b/compiler/rustc_const_eval/src/interpret/place.rs @@ -642,7 +642,7 @@ where // avoid force_allocation. let src = match self.read_immediate_raw(src)? { Ok(src_val) => { - assert!(!src.layout.is_unsized(), "cannot have unsized immediates"); + assert!(!src.layout.is_unsized(), "cannot copy unsized immediates"); assert!( !dest.layout.is_unsized(), "the src is sized, so the dest must also be sized" diff --git a/compiler/rustc_const_eval/src/interpret/projection.rs b/compiler/rustc_const_eval/src/interpret/projection.rs index 742339f2b0a..16ce5bc7175 100644 --- a/compiler/rustc_const_eval/src/interpret/projection.rs +++ b/compiler/rustc_const_eval/src/interpret/projection.rs @@ -100,6 +100,8 @@ where // This makes several assumptions about what layouts we will encounter; we match what // codegen does as good as we can (see `extract_field` in `rustc_codegen_ssa/src/mir/operand.rs`). let field_val: Immediate<_> = match (*base, base.layout.abi) { + // if the entire value is uninit, then so is the field (can happen in ConstProp) + (Immediate::Uninit, _) => Immediate::Uninit, // the field contains no information, can be left uninit _ if field_layout.is_zst() => Immediate::Uninit, // the field covers the entire type @@ -124,6 +126,7 @@ where b_val }) } + // everything else is a bug _ => span_bug!( self.cur_span(), "invalid field access on immediate {}, layout {:#?}", -- cgit 1.4.1-3-g733a5