From 16c71886c9ed143a22890f99c59deea37b157fa8 Mon Sep 17 00:00:00 2001 From: Simonas Kazlauskas Date: Sun, 14 Feb 2021 17:12:14 +0200 Subject: [PATCH] Set path of the compile unit to the source directory As part of the effort to implement split dwarf debug info, we ended up setting the compile unit location to the output directory rather than the source directory. Furthermore, it seems like we failed to remap the prefixes for this as well! The desired behaviour is to instead set the `DW_AT_GNU_dwo_name` to a path relative to compiler's working directory. This still allows debuggers to find the split dwarf files, while not changing the behaviour of the code that is compiling with regular debug info, and not changing the compiler's behaviour with regards to reproducibility. Fixes #82074 --- compiler/rustc_codegen_llvm/src/back/write.rs | 2 +- .../src/debuginfo/metadata.rs | 19 +++++++++++-------- compiler/rustc_codegen_ssa/src/back/write.rs | 2 +- compiler/rustc_session/src/config.rs | 11 ----------- 4 files changed, 13 insertions(+), 21 deletions(-) diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs index 8b737c9a2e5..8d945709da4 100644 --- a/compiler/rustc_codegen_llvm/src/back/write.rs +++ b/compiler/rustc_codegen_llvm/src/back/write.rs @@ -93,7 +93,7 @@ pub fn create_informational_target_machine(sess: &Session) -> &'static mut llvm: pub fn create_target_machine(tcx: TyCtxt<'_>, mod_name: &str) -> &'static mut llvm::TargetMachine { let split_dwarf_file = if tcx.sess.target_can_use_split_dwarf() { tcx.output_filenames(LOCAL_CRATE) - .split_dwarf_filename(tcx.sess.split_debuginfo(), Some(mod_name)) + .split_dwarf_path(tcx.sess.split_debuginfo(), Some(mod_name)) } else { None }; diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs index 6e7c0b3e347..d935fc83b72 100644 --- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs +++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs @@ -979,7 +979,7 @@ pub fn compile_unit_metadata( // The OSX linker has an idiosyncrasy where it will ignore some debuginfo // if multiple object files with the same `DW_AT_name` are linked together. // As a workaround we generate unique names for each object file. Those do - // not correspond to an actual source file but that should be harmless. + // not correspond to an actual source file but that is harmless. if tcx.sess.target.is_like_osx { name_in_debuginfo.push("@"); name_in_debuginfo.push(codegen_unit_name); @@ -992,17 +992,17 @@ pub fn compile_unit_metadata( let producer = format!("clang LLVM ({})", rustc_producer); let name_in_debuginfo = name_in_debuginfo.to_string_lossy(); + let work_dir = tcx.sess.working_dir.0.to_string_lossy(); let flags = "\0"; - let out_dir = &tcx.output_filenames(LOCAL_CRATE).out_directory; let split_name = if tcx.sess.target_can_use_split_dwarf() { tcx.output_filenames(LOCAL_CRATE) - .split_dwarf_filename(tcx.sess.split_debuginfo(), Some(codegen_unit_name)) + .split_dwarf_path(tcx.sess.split_debuginfo(), Some(codegen_unit_name)) + .map(|f| out_dir.join(f)) } else { None } .unwrap_or_default(); - let out_dir = out_dir.to_str().unwrap(); let split_name = split_name.to_str().unwrap(); // FIXME(#60020): @@ -1024,12 +1024,12 @@ pub fn compile_unit_metadata( assert!(tcx.sess.opts.debuginfo != DebugInfo::None); unsafe { - let file_metadata = llvm::LLVMRustDIBuilderCreateFile( + let compile_unit_file = llvm::LLVMRustDIBuilderCreateFile( debug_context.builder, name_in_debuginfo.as_ptr().cast(), name_in_debuginfo.len(), - out_dir.as_ptr().cast(), - out_dir.len(), + work_dir.as_ptr().cast(), + work_dir.len(), llvm::ChecksumKind::None, ptr::null(), 0, @@ -1038,12 +1038,15 @@ pub fn compile_unit_metadata( let unit_metadata = llvm::LLVMRustDIBuilderCreateCompileUnit( debug_context.builder, DW_LANG_RUST, - file_metadata, + compile_unit_file, producer.as_ptr().cast(), producer.len(), tcx.sess.opts.optimize != config::OptLevel::No, flags.as_ptr().cast(), 0, + // NB: this doesn't actually have any perceptible effect, it seems. LLVM will instead + // put the path supplied to `MCSplitDwarfFile` into the debug info of the final + // output(s). split_name.as_ptr().cast(), split_name.len(), kind, diff --git a/compiler/rustc_codegen_ssa/src/back/write.rs b/compiler/rustc_codegen_ssa/src/back/write.rs index 6aef5cb535a..cb493f51677 100644 --- a/compiler/rustc_codegen_ssa/src/back/write.rs +++ b/compiler/rustc_codegen_ssa/src/back/write.rs @@ -288,7 +288,7 @@ impl TargetMachineFactoryConfig { module_name: &str, ) -> TargetMachineFactoryConfig { let split_dwarf_file = if cgcx.target_can_use_split_dwarf { - cgcx.output_filenames.split_dwarf_filename(cgcx.split_debuginfo, Some(module_name)) + cgcx.output_filenames.split_dwarf_path(cgcx.split_debuginfo, Some(module_name)) } else { None }; diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs index 210dbb0ee99..86a1f1b7adb 100644 --- a/compiler/rustc_session/src/config.rs +++ b/compiler/rustc_session/src/config.rs @@ -667,17 +667,6 @@ impl OutputFilenames { path } - /// Returns the name of the Split DWARF file - this can differ depending on which Split DWARF - /// mode is being used, which is the logic that this function is intended to encapsulate. - pub fn split_dwarf_filename( - &self, - split_debuginfo_kind: SplitDebuginfo, - cgu_name: Option<&str>, - ) -> Option { - self.split_dwarf_path(split_debuginfo_kind, cgu_name) - .map(|path| path.strip_prefix(&self.out_directory).unwrap_or(&path).to_path_buf()) - } - /// Returns the path for the Split DWARF file - this can differ depending on which Split DWARF /// mode is being used, which is the logic that this function is intended to encapsulate. pub fn split_dwarf_path(