From 07e7823c01be1733df2480de19fbbe6b8e9384cf Mon Sep 17 00:00:00 2001 From: Dan Aloni Date: Wed, 2 Sep 2020 10:40:56 +0300 Subject: pretty: trim paths of unique symbols If a symbol name can only be imported from one place for a type, and as long as it was not glob-imported anywhere in the current crate, we can trim its printed path and print only the name. This has wide implications on error messages with types, for example, shortening `std::vec::Vec` to just `Vec`, as long as there is no other `Vec` importable anywhere. This adds a new '-Z trim-diagnostic-paths=false' option to control this feature. On the good path, with no diagnosis printed, we should try to avoid issuing this query, so we need to prevent trimmed_def_paths query on several cases. This change also relies on a previous commit that differentiates between `Debug` and `Display` on various rustc types, where the latter is trimmed and presented to the user and the former is not. --- compiler/rustc_codegen_ssa/src/mir/block.rs | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'compiler/rustc_codegen_ssa/src/mir') diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs index 6eb80157239..d448fa165e0 100644 --- a/compiler/rustc_codegen_ssa/src/mir/block.rs +++ b/compiler/rustc_codegen_ssa/src/mir/block.rs @@ -16,6 +16,7 @@ use rustc_middle::mir; use rustc_middle::mir::interpret::{AllocId, ConstValue, Pointer, Scalar}; use rustc_middle::mir::AssertKind; use rustc_middle::ty::layout::{FnAbiExt, HasTyCtxt}; +use rustc_middle::ty::print::with_no_trimmed_paths; use rustc_middle::ty::{self, Instance, Ty, TypeFoldable}; use rustc_span::source_map::Span; use rustc_span::{sym, Symbol}; @@ -479,14 +480,16 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { UninitValid => !layout.might_permit_raw_init(bx, /*zero:*/ false).unwrap(), }; if do_panic { - let msg_str = if layout.abi.is_uninhabited() { - // Use this error even for the other intrinsics as it is more precise. - format!("attempted to instantiate uninhabited type `{}`", ty) - } else if intrinsic == ZeroValid { - format!("attempted to zero-initialize type `{}`, which is invalid", ty) - } else { - format!("attempted to leave type `{}` uninitialized, which is invalid", ty) - }; + let msg_str = with_no_trimmed_paths(|| { + if layout.abi.is_uninhabited() { + // Use this error even for the other intrinsics as it is more precise. + format!("attempted to instantiate uninhabited type `{}`", ty) + } else if intrinsic == ZeroValid { + format!("attempted to zero-initialize type `{}`, which is invalid", ty) + } else { + format!("attempted to leave type `{}` uninitialized, which is invalid", ty) + } + }); let msg = bx.const_str(Symbol::intern(&msg_str)); let location = self.get_caller_location(bx, span).immediate(); -- cgit 1.4.1-3-g733a5