[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. Do you have any interest in seeing if gdb could/would be fixed to handle the imported declaration style? Might be worth knowing if that's feasible, if they have some ideas about if/why that would be a bad idea, etc. Repository: rG LLVM Github Monorepo CHANGES

[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. In D103131#2835981 , @kamleshbhalui wrote: > In D103131#2835909 , @dblaikie > wrote: > >> In D103131#2835702 , >> @kamleshbhalui wrote: >>

[PATCH] D103131: support debug info for alias variable

kamleshbhalui added a comment. In D103131#2835909 , @dblaikie wrote: > In D103131#2835702 , @kamleshbhalui > wrote: > >> Here is what we get when we replace int with float. >> >> $lldb-11 ./a.out >> (lldb)

[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. In D103131#2835702 , @kamleshbhalui wrote: > Here is what we get when we replace int with float. > > $lldb-11 ./a.out > (lldb) target create "./a.out" > Current executable set to >

[PATCH] D103131: support debug info for alias variable

kamleshbhalui added a comment. Here is what we get when we replace int with float. $lldb-11 ./a.out (lldb) target create "./a.out" Current executable set to '/folk/kkumar/tcllvm/llvm-build-lldb-rel/bin/a.out' (x86_64). (lldb) b main Breakpoint 1: where = a.out`main + 4 at

[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. In D103131#2835004 , @kamleshbhalui wrote: > In D103131#2834744 , @dblaikie > wrote: > >> Huh, that surprises me - guess gdb favors checking the symbol first. I guess >> maybe it is

[PATCH] D103131: support debug info for alias variable

kamleshbhalui added a comment. In D103131#2834744 , @dblaikie wrote: > Huh, that surprises me - guess gdb favors checking the symbol first. I guess > maybe it is using something that determines that that symbol comes from the > file with debug info -

[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. Huh, that surprises me - guess gdb favors checking the symbol first. I guess maybe it is using something that determines that that symbol comes from the file with debug info - because on a similar test case (one file without debug info, defining some global variable

[PATCH] D103131: support debug info for alias variable

kamleshbhalui added a comment. In D103131#2815386 , @probinson wrote: >>> 0x002a: DW_TAG_variable >>> DW_AT_name ("oldname") >>> DW_AT_type (0x003f "int") >>> DW_AT_external

RE: [PATCH] D103131: support debug info for alias variable

> > 0x002a: DW_TAG_variable > > DW_AT_name ("oldname") > > DW_AT_type (0x003f "int") > > DW_AT_external (true) > > DW_AT_decl_file ("/folk/kkumar/tcllvm/llvm-build-lldb- > rel/bin/test.c") > >

[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. In D103131#2814595 , @kamleshbhalui wrote: > In D103131#2814015 , @dblaikie > wrote: > >> In D103131#2811969 , >> @kamleshbhalui wrote: >>

[PATCH] D103131: support debug info for alias variable

kamleshbhalui added a comment. In D103131#2814015 , @dblaikie wrote: > In D103131#2811969 , @kamleshbhalui > wrote: > >> In D103131#2811220 , @dblaikie >> wrote: >> >>>

[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. In D103131#2811969 , @kamleshbhalui wrote: > In D103131#2811220 , @dblaikie > wrote: > >> Any idea if the GDB test suite covers this functionality? I'd hope so, but >> maybe it

[PATCH] D103131: support debug info for alias variable

kamleshbhalui added a comment. In D103131#2811220 , @dblaikie wrote: > Any idea if the GDB test suite covers this functionality? I'd hope so, but > maybe it doesn't. > > But yeah, at the moment I don't have any great reason to avoid the imported >

[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. Any idea if the GDB test suite covers this functionality? I'd hope so, but maybe it doesn't. But yeah, at the moment I don't have any great reason to avoid the imported declaration form - so happy to go with that. Repository: rG LLVM Github Monorepo CHANGES SINCE

[PATCH] D103131: support debug info for alias variable

kamleshbhalui added a comment. In D103131#2791881 , @dblaikie wrote: > In D103131#2789493 , @probinson > wrote: > >>> Mixed feelings - somewhat in favor of "do the thing that's probably already >>> fairly

[PATCH] D103131: support debug info for alias variable

probinson added a comment. In D103131#2792364 , @dblaikie wrote: > I will say, as the person who implemented DW_TAG_imported_declaration support > in Clang - it's a bit not great/unfortunate (in part because we currently > have to emit them for all

[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. In D103131#2792159 , @probinson wrote: > In D103131#2791881 , @dblaikie > wrote: > >> In D103131#2789493 , @probinson >> wrote: >> Mixed

[PATCH] D103131: support debug info for alias variable

probinson added a comment. In D103131#2791881 , @dblaikie wrote: > In D103131#2789493 , @probinson > wrote: > >>> Mixed feelings - somewhat in favor of "do the thing that's probably already >>> fairly

[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. In D103131#2789493 , @probinson wrote: >> Mixed feelings - somewhat in favor of "do the thing that's probably already >> fairly tested/known to work" (GCC's thing). But open to the idea that that >> approach has problems, for

[PATCH] D103131: support debug info for alias variable

probinson added a comment. Of course, if it turns out that gdb can't handle the imported_declaration, we might end up having to do this two different ways under the tuning option. I'd *really* prefer not to do that though, and I'd argue it's a gdb bug if it cannot understand

[PATCH] D103131: support debug info for alias variable

probinson added a comment. In D103131#2789493 , @probinson wrote: >> Mixed feelings - somewhat in favor of "do the thing that's probably already >> fairly tested/known to work" (GCC's thing). But open to the idea that that >> approach has problems, for

[PATCH] D103131: support debug info for alias variable

probinson added a comment. > Mixed feelings - somewhat in favor of "do the thing that's probably already > fairly tested/known to work" (GCC's thing). But open to the idea that that > approach has problems, for sure. "Known to work" for whom? gdb, sure, because gcc/gdb cooperate on many

[PATCH] D103131: support debug info for alias variable

kamleshbhalui added a comment. $cat test.h int oldname; $cat test.c #include "test.h" int oldname; __asm__ ( "movq oldname, %rsp\n\t" ); extern int newname __attribute__((alias("oldname"))); debug info from gcc: test.o: file format elf64-x86-64 .debug_info contents: 0x: Compile

[PATCH] D103131: support debug info for alias variable

dblaikie added inline comments. Comment at: clang/lib/CodeGen/CGDebugInfo.cpp:4957 + auto Loc = getLineNumber(D->getLocation()); + DBuilder.createGlobalVariableExpression( + DContext, Name, StringRef(), Unit, Loc, Ty, probinson wrote: > I wasn't saying

[PATCH] D103131: support debug info for alias variable

probinson added inline comments. Comment at: clang/lib/CodeGen/CGDebugInfo.cpp:4957 + auto Loc = getLineNumber(D->getLocation()); + DBuilder.createGlobalVariableExpression( + DContext, Name, StringRef(), Unit, Loc, Ty, I wasn't saying that gcc did the

[PATCH] D103131: support debug info for alias variable

kamleshbhalui updated this revision to Diff 348501. kamleshbhalui added a comment. matching gcc behavior Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D103131/new/ https://reviews.llvm.org/D103131 Files: clang/lib/CodeGen/CGDebugInfo.cpp

[PATCH] D103131: support debug info for alias variable

kamleshbhalui updated this revision to Diff 348160. kamleshbhalui added a comment. match gcc behavior Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D103131/new/ https://reviews.llvm.org/D103131 Files: clang/lib/CodeGen/CGDebugInfo.cpp

[PATCH] D103131: support debug info for alias variable

probinson added a comment. In D103131#2780997 , @dblaikie wrote: > Looks like GCC emits aliases as a `DW_TAG_variable` without a location, not > as a `DW_TAG_imported_declaration` and marks it external; this works only because gdb will look up the ELF

[PATCH] D103131: support debug info for alias variable

kamleshbhalui updated this revision to Diff 347883. kamleshbhalui retitled this revision from "support debug info for alias variable " to "support debug info for alias variable". kamleshbhalui added a comment. removed unnecessary code. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST

[PATCH] D103131: support debug info for alias variable

umesh.kalappa0 added inline comments. Comment at: clang/lib/CodeGen/CGDebugInfo.cpp:4949 +void CGDebugInfo::EmitGlobalAlias(llvm::GlobalAlias *Var, const VarDecl *D) { + if (!CGM.getCodeGenOpts().hasReducedDebugInfo()) +return; check is redundant ,no

[PATCH] D103131: support debug info for alias variable

umesh.kalappa0 added inline comments. Comment at: clang/lib/CodeGen/CGDebugInfo.cpp:4948 +void CGDebugInfo::EmitGlobalAlias(llvm::GlobalAlias *Var, const VarDecl *D) { + if (!CGM.getCodeGenOpts().hasReducedDebugInfo()) Var is never used in the EmitGlobalAlias

[PATCH] D103131: support debug info for alias variable

kamleshbhalui added a comment. In D103131#2780997 , @dblaikie wrote: > Looks like GCC emits aliases as a `DW_TAG_variable` without a location, not > as a `DW_TAG_imported_declaration` - what gave you the inspiration to do it > in this way? (I think

[PATCH] D103131: support debug info for alias variable

dblaikie added a comment. Looks like GCC emits aliases as a `DW_TAG_variable` without a location, not as a `DW_TAG_imported_declaration` - what gave you the inspiration to do it in this way? (I think it's probably good, but DWARF doesn't lend itself to novelty so much... can be good to stick

[PATCH] D103131: support debug info for alias variable

kamleshbhalui created this revision. kamleshbhalui added reviewers: dblaikie, aprantl, probinson. kamleshbhalui added a project: LLVM. Herald added a subscriber: jeroen.dobbelaere. kamleshbhalui requested review of this revision. Herald added a project: clang. Herald added a subscriber: