llvm: dwo only emitted when object code emitted

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -765,11 +765,21 @@ pub(crate) unsafe fn codegen(
  drop(handlers);
  }
 
+ // `.dwo` files are only emitted if:
+ //
+ // - Object files are being emitted (i.e. bitcode only or metadata only compilations will not
+ // produce dwarf objects, even if otherwise enabled)
+ // - Target supports Split DWARF
+ // - Split debuginfo is enabled
+ // - Split DWARF kind is `split` (i.e. debuginfo is split into `.dwo` files, not different
+ // sections in the `.o` files).
+ let dwarf_object_emitted = matches!(config.emit_obj, EmitObj::ObjectCode(_))
+ && cgcx.target_can_use_split_dwarf
+ && cgcx.split_debuginfo != SplitDebuginfo::Off
+ && cgcx.split_dwarf_kind == SplitDwarfKind::Split;
  Ok(module.into_compiled_module(
  config.emit_obj != EmitObj::None,
- cgcx.target_can_use_split_dwarf
- && cgcx.split_debuginfo != SplitDebuginfo::Off
- && cgcx.split_dwarf_kind == SplitDwarfKind::Split,
+ dwarf_object_emitted,
  config.emit_bc,
  &cgcx.output_filenames,
  ))

src/test/run-make-fulldeps/split-debuginfo/Makefile

@@ -3,7 +3,7 @@ include ../tools.mk
 all: off packed unpacked
 
 ifeq ($(UNAME),Darwin)
-# If disabled, don't run dsymutil
+# If disabled, don't run `dsymutil`.
 off:
  rm -rf $(TMPDIR)/*.dSYM
  $(RUSTC) foo.rs -g -C split-debuginfo=off
@@ -29,98 +29,280 @@ unpacked:
  [ ! -d $(TMPDIR)/foo.dSYM ]
 else
 ifdef IS_WINDOWS
-# Windows only supports =packed
+# Windows only supports packed debuginfo - nothing to test.
 off:
 packed:
 unpacked:
 else
+# Some non-Windows, non-Darwin platforms are not stable, and some are.
 ifeq ($(UNAME),Linux)
  UNSTABLEOPTS :=
 else
  UNSTABLEOPTS := -Zunstable-options
 endif
 
+# - Debuginfo in `.o` files
+# - `.o` deleted
+# - `.dwo` never created
+# - `.dwp` never created
 off:
  $(RUSTC) foo.rs -g -C $(UNSTABLEOPTS) split-debuginfo=off
  [ ! -f $(TMPDIR)/*.dwp ]
  [ ! -f $(TMPDIR)/*.dwo ]
-
  $(RUSTC) foo.rs -g
  [ ! -f $(TMPDIR)/*.dwp ]
  [ ! -f $(TMPDIR)/*.dwo ]
 
-packed: packed-split packed-single
+packed: packed-split packed-single packed-lto packed-remapped packed-crosscrate
 
+# - Debuginfo in `.dwo` files
+# - `.o` deleted
+# - `.dwo` deleted
+# - `.dwp` present
 packed-split:
  $(RUSTC) foo.rs -g $(UNSTABLEOPTS) -C split-debuginfo=packed -Zsplit-dwarf-kind=split
- ls $(TMPDIR)/*.dwp
- rm -rf $(TMPDIR)/*.dwp $(TMPDIR)/*.dwo
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+ rm $(TMPDIR)/foo.dwp
+ rm $(TMPDIR)/$(call BIN,foo)
 
+# - Debuginfo in `.o` files
+# - `.o` deleted
+# - `.dwo` never created
+# - `.dwp` present
 packed-single:
  $(RUSTC) foo.rs -g $(UNSTABLEOPTS) -C split-debuginfo=packed -Zsplit-dwarf-kind=single
- ls $(TMPDIR)/*.dwp
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+ rm $(TMPDIR)/foo.dwp
+ rm $(TMPDIR)/$(call BIN,foo)
+
+packed-lto: packed-lto-split packed-lto-single
+
+# - rmeta file added to rlib, no object files are generated and thus no debuginfo is generated
+# - `.o` never created
+# - `.dwo` never created
+# - `.dwp` never created
+packed-lto-split:
+ $(RUSTC) baz.rs -g $(UNSTABLEOPTS) -Csplit-debuginfo=packed -Zsplit-dwarf-kind=split \
+ --crate-type=rlib -Clinker-plugin-lto
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ rm $(TMPDIR)/libbaz.rlib
+
+# - rmeta file added to rlib, no object files are generated and thus no debuginfo is generated
+# - `.o` never created
+# - `.dwo` never created
+# - `.dwp` never created
+packed-lto-single:
+ $(RUSTC) baz.rs -g $(UNSTABLEOPTS) -Csplit-debuginfo=packed -Zsplit-dwarf-kind=single \
+ --crate-type=rlib -Clinker-plugin-lto
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
  ls $(TMPDIR)/*.dwo && exit 1 || exit 0
- rm -rf $(TMPDIR)/*.dwp
+ ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ rm $(TMPDIR)/libbaz.rlib
 
 packed-remapped: packed-remapped-split packed-remapped-single
 
+# - Debuginfo in `.dwo` files
+# - `.o` and binary refer to remapped `.dwo` paths which do not exist
+# - `.o` deleted
+# - `.dwo` deleted
+# - `.dwp` present
 packed-remapped-split:
  $(RUSTC) $(UNSTABLEOPTS) -C split-debuginfo=packed -C debuginfo=2 \
  -Z split-dwarf-kind=split --remap-path-prefix $(TMPDIR)=/a foo.rs -g
  objdump -Wi $(TMPDIR)/foo | grep DW_AT_GNU_dwo_name | (! grep $(TMPDIR)) || exit 1
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+ rm $(TMPDIR)/foo.dwp
+ rm $(TMPDIR)/$(call BIN,foo)
 
+# - Debuginfo in `.o` files
+# - `.o` and binary refer to remapped `.o` paths which do not exist
+# - `.o` deleted
+# - `.dwo` never created
+# - `.dwp` present
 packed-remapped-single:
  $(RUSTC) $(UNSTABLEOPTS) -C split-debuginfo=packed -C debuginfo=2 \
  -Z split-dwarf-kind=single --remap-path-prefix $(TMPDIR)=/a foo.rs -g
  objdump -Wi $(TMPDIR)/foo | grep DW_AT_GNU_dwo_name | (! grep $(TMPDIR)) || exit 1
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+ rm $(TMPDIR)/foo.dwp
+ rm $(TMPDIR)/$(call BIN,foo)
 
 packed-crosscrate: packed-crosscrate-split packed-crosscrate-single
 
+# - Debuginfo in `.dwo` files
+# - (bar) `.rlib` file created, contains `.dwo`
+# - (bar) `.o` deleted
+# - (bar) `.dwo` deleted
+# - (bar) `.dwp` never created
+# - (main) `.o` deleted
+# - (main) `.dwo` deleted
+# - (main) `.dwp` present
 packed-crosscrate-split:
  $(RUSTC) --crate-type lib $(UNSTABLEOPTS) -C split-debuginfo=packed \
  -Zsplit-dwarf-kind=split -C debuginfo=2 -g bar.rs
  ls $(TMPDIR)/*.rlib
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
  ls $(TMPDIR)/*.dwo && exit 1 || exit 0
  ls $(TMPDIR)/*.dwp && exit 1 || exit 0
- $(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib -Z unstable-options $(UNSTABLEOPTS) \
+ $(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib $(UNSTABLEOPTS) \
  -C split-debuginfo=packed -Zsplit-dwarf-kind=split -C debuginfo=2 -g main.rs
- rm $(TMPDIR)/*.dwo
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
  rm $(TMPDIR)/main.dwp
  rm $(TMPDIR)/$(call BIN,main)
 
+# - Debuginfo in `.o` files
+# - (bar) `.rlib` file created, contains `.o`
+# - (bar) `.o` deleted
+# - (bar) `.dwo` never created
+# - (bar) `.dwp` never created
+# - (main) `.o` deleted
+# - (main) `.dwo` never created
+# - (main) `.dwp` present
 packed-crosscrate-single:
  $(RUSTC) --crate-type lib $(UNSTABLEOPTS) -C split-debuginfo=packed \
  -Zsplit-dwarf-kind=single -C debuginfo=2 -g bar.rs
  ls $(TMPDIR)/*.rlib
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
  ls $(TMPDIR)/*.dwo && exit 1 || exit 0
  ls $(TMPDIR)/*.dwp && exit 1 || exit 0
- $(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib -Z unstable-options $(UNSTABLEOPTS) \
+ $(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib $(UNSTABLEOPTS) \
  -C split-debuginfo=packed -Zsplit-dwarf-kind=single -C debuginfo=2 -g main.rs
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
  ls $(TMPDIR)/*.dwo && exit 1 || exit 0
  rm $(TMPDIR)/main.dwp
  rm $(TMPDIR)/$(call BIN,main)
 
-unpacked: unpacked-split unpacked-single unpacked-remapped-split unpacked-remapped-single
+unpacked: unpacked-split unpacked-single unpacked-lto unpacked-remapped unpacked-crosscrate
 
+# - Debuginfo in `.dwo` files
+# - `.o` deleted
+# - `.dwo` present
+# - `.dwp` never created
 unpacked-split:
  $(RUSTC) foo.rs -g $(UNSTABLEOPTS) -C split-debuginfo=unpacked -Zsplit-dwarf-kind=split
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ rm $(TMPDIR)/*.dwo
  ls $(TMPDIR)/*.dwp && exit 1 || exit 0
- ls $(TMPDIR)/*.dwo
- rm -rf $(TMPDIR)/*.dwp $(TMPDIR)/*.dwo
+ rm $(TMPDIR)/$(call BIN,foo)
 
+# - Debuginfo in `.o` files
+# - `.o` present
+# - `.dwo` never created
+# - `.dwp` never created
 unpacked-single:
  $(RUSTC) foo.rs -g $(UNSTABLEOPTS) -C split-debuginfo=unpacked -Zsplit-dwarf-kind=single
+ ls $(TMPDIR)/*.o
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ rm $(TMPDIR)/$(call BIN,foo)
+
+unpacked-lto: packed-lto-split packed-lto-single
+
+# - rmeta file added to rlib, no object files are generated and thus no debuginfo is generated
+# - `.o` never created
+# - `.dwo` never created
+# - `.dwp` never created
+unpacked-lto-split:
+ $(RUSTC) baz.rs -g $(UNSTABLEOPTS) -Csplit-debuginfo=unpacked -Zsplit-dwarf-kind=split \
+ --crate-type=rlib -Clinker-plugin-lto
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
  ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ rm $(TMPDIR)/libbaz.rlib
+
+# - rmeta file added to rlib, no object files are generated and thus no debuginfo is generated
+# - `.o` never created
+# - `.dwo` never created
+# - `.dwp` never created
+unpacked-lto-single:
+ $(RUSTC) baz.rs -g $(UNSTABLEOPTS) -Csplit-debuginfo=unpacked -Zsplit-dwarf-kind=single \
+ --crate-type=rlib -Clinker-plugin-lto
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
  ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ rm $(TMPDIR)/libbaz.rlib
+
+unpacked-remapped: unpacked-remapped-split unpacked-remapped-single
 
+# - Debuginfo in `.dwo` files
+# - `.o` and binary refer to remapped `.dwo` paths which do not exist
+# - `.o` deleted
+# - `.dwo` present
+# - `.dwp` never created
 unpacked-remapped-split:
  $(RUSTC) $(UNSTABLEOPTS) -C split-debuginfo=unpacked -C debuginfo=2 \
  -Z split-dwarf-kind=split --remap-path-prefix $(TMPDIR)=/a foo.rs -g
  objdump -Wi $(TMPDIR)/foo | grep DW_AT_GNU_dwo_name | (! grep $(TMPDIR)) || exit 1
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ rm $(TMPDIR)/*.dwo
+ ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ rm $(TMPDIR)/$(call BIN,foo)
 
+# - Debuginfo in `.o` files
+# - `.o` and binary refer to remapped `.o` paths which do not exist
+# - `.o` present
+# - `.dwo` never created
+# - `.dwp` never created
 unpacked-remapped-single:
  $(RUSTC) $(UNSTABLEOPTS) -C split-debuginfo=unpacked -C debuginfo=2 \
  -Z split-dwarf-kind=single --remap-path-prefix $(TMPDIR)=/a foo.rs -g
  objdump -Wi $(TMPDIR)/foo | grep DW_AT_GNU_dwo_name | (! grep $(TMPDIR)) || exit 1
+ ls $(TMPDIR)/*.o
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ rm $(TMPDIR)/$(call BIN,foo)
+
+unpacked-crosscrate: packed-crosscrate-split packed-crosscrate-single
+
+# - Debuginfo in `.dwo` files
+# - (bar) `.rlib` file created, contains `.dwo`
+# - (bar) `.o` deleted
+# - (bar) `.dwo` present
+# - (bar) `.dwp` never created
+# - (main) `.o` deleted
+# - (main) `.dwo` present
+# - (main) `.dwp` never created
+unpacked-crosscrate-split:
+ $(RUSTC) --crate-type lib $(UNSTABLEOPTS) -C split-debuginfo=unpacked \
+ -Zsplit-dwarf-kind=split -C debuginfo=2 -g bar.rs
+ ls $(TMPDIR)/*.rlib
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwo
+ ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ $(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib $(UNSTABLEOPTS) \
+ -C split-debuginfo=unpacked -Zsplit-dwarf-kind=split -C debuginfo=2 -g main.rs
+ ls $(TMPDIR)/*.o && exit 1 || exit 0
+ rm $(TMPDIR)/*.dwo
+ ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ rm $(TMPDIR)/$(call BIN,main)
+
+# - Debuginfo in `.o` files
+# - (bar) `.rlib` file created, contains `.o`
+# - (bar) `.o` present
+# - (bar) `.dwo` never created
+# - (bar) `.dwp` never created
+# - (main) `.o` present
+# - (main) `.dwo` never created
+# - (main) `.dwp` never created
+unpacked-crosscrate-single:
+ $(RUSTC) --crate-type lib $(UNSTABLEOPTS) -C split-debuginfo=unpacked \
+ -Zsplit-dwarf-kind=single -C debuginfo=2 -g bar.rs
+ ls $(TMPDIR)/*.rlib
+ ls $(TMPDIR)/*.o
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ $(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib $(UNSTABLEOPTS) \
+ -C split-debuginfo=unpacked -Zsplit-dwarf-kind=single -C debuginfo=2 -g main.rs
+ ls $(TMPDIR)/*.o
+ ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+ ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+ rm $(TMPDIR)/$(call BIN,main)
 endif
 endif

src/test/run-make-fulldeps/split-debuginfo/baz.rs

@@ -0,0 +1 @@
+// empty