From 1cf9be98cdc2d2753b11dd71d83c03c82897b006 Mon Sep 17 00:00:00 2001 From: David Wood Date: Thu, 21 Jul 2022 16:19:22 +0100 Subject: [PATCH] ssa: implement `#[collapse_debuginfo]` Debuginfo line information for macro invocations are collapsed by default - line information are replaced by the line of the outermost expansion site. Using `-Zdebug-macros` disables this behaviour. When the `collapse_debuginfo` feature is enabled, the default behaviour is reversed so that debuginfo is not collapsed by default. In addition, the `#[collapse_debuginfo]` attribute is available and can be applied to macro definitions which will then have their line information collapsed. Signed-off-by: David Wood --- src/debuginfo/line_info.rs | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/src/debuginfo/line_info.rs b/src/debuginfo/line_info.rs index 3ad0c420eaf..463de6a91c7 100644 --- a/src/debuginfo/line_info.rs +++ b/src/debuginfo/line_info.rs @@ -68,9 +68,9 @@ pub(crate) fn get_span_loc( ) -> (Lrc, u64, u64) { // Based on https://github.com/rust-lang/rust/blob/e369d87b015a84653343032833d65d0545fd3f26/src/librustc_codegen_ssa/mir/mod.rs#L116-L131 // In order to have a good line stepping behavior in debugger, we overwrite debug - // locations of macro expansions with that of the outermost expansion site - // (unless the crate is being compiled with `-Z debug-macros`). - let span = if !span.from_expansion() || tcx.sess.opts.unstable_opts.debug_macros { + // locations of macro expansions with that of the outermost expansion site (when the macro is + // annotated with `#[collapse_debuginfo]` or when `-Zdebug-macros` is provided). + let span = if tcx.should_collapse_debuginfo(span) { span } else { // Walk up the macro expansion chain until we reach a non-expanded span.