Launchpad has imported 5 comments from the remote bug at https://sourceware.org/bugzilla/show_bug.cgi?id=31580.
If you reply to an imported comment from within Launchpad, your comment will be sent to the remote bug automatically. Read more about Launchpad's inter-bugtracker facilities at https://help.launchpad.net/InterBugTracking. ------------------------------------------------------------------------ On 2024-03-30T00:23:30+00:00 Zixing Liu wrote: Created attachment 15447 Minimal reproducible example (D source code) Hi there, I have discovered a D class type resolution regression since GDB 10 (it was working properly in GDB 9). Please find the reproducer in the file attached. You can compile the source code using either GDC or LDC2 (both can reproduce this issue): gdc -g -O0 t.d -o t To reproduce the bug, set the breakpoint to t.d:10 and examine the `i` global variable (using `p t.i`). GDB will then complain that "'t.i' has unknown type; cast it to its declared type." I found a workaround to this problem by using `p (uv*)_D1t1iCQf2uv`, but obviously, this is non-ideal: the developer may not know the mangled variable name easily. Since this looks like a regression, I did a simple `git bisect` that led me to this commit: https://sourceware.org/git/?p=binutils- gdb.git;a=commit;h=727b7b1864973c2645a554727afd0eaf1303673a. I am unsure how demangle changes could affect the type resolution (maybe it's because GDB got confused about which entity to decode?) Reply at: https://bugs.launchpad.net/ubuntu/+source/gdb/+bug/2059856/comments/0 ------------------------------------------------------------------------ On 2024-03-30T19:30:45+00:00 Tromey-b wrote: Computing the "physname" decides that the symbol should be named: (top-gdb) p physname $37 = 0x2c70490 "_D1t1iCQf2uv" ... which is plainly wrong. Reply at: https://bugs.launchpad.net/ubuntu/+source/gdb/+bug/2059856/comments/1 ------------------------------------------------------------------------ On 2024-03-30T19:36:27+00:00 Tromey-b wrote: Ok, so while gdb's symbol reader is still really wrong here -- this physname stuff is pretty broken -- the root cause of this particular bug is also that libiberty does not auto-demangle D symbols. You can see this on the command line: prentzel. c++filt _D1t1iCQf2uv _D1t1iCQf2uv prentzel. c++filt -s dlang _D1t1iCQf2uv t.i To my eye this seems to be an oversight in cplus-dem.c, where the D code follows some earlier code; but perhaps the author didn't realize that the reason the Ada code does not check AUTO_DEMANGLING is that the Ada encoding isn't unambiguous in the way the D encoding is. Reply at: https://bugs.launchpad.net/ubuntu/+source/gdb/+bug/2059856/comments/2 ------------------------------------------------------------------------ On 2024-03-30T19:49:00+00:00 Tromey-b wrote: Testing a patch. Reply at: https://bugs.launchpad.net/ubuntu/+source/gdb/+bug/2059856/comments/3 ------------------------------------------------------------------------ On 2024-03-30T20:10:51+00:00 Tromey-b wrote: https://sourceware.org/pipermail/gdb-patches/2024-March/207686.html Reply at: https://bugs.launchpad.net/ubuntu/+source/gdb/+bug/2059856/comments/4 ** Changed in: gdb Status: Unknown => Confirmed ** Changed in: gdb Importance: Unknown => Medium -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to gdb in Ubuntu. https://bugs.launchpad.net/bugs/2059856 Title: gdb 10.0 fails to examine any global variables in D programs Status in gdb: Confirmed Status in gdb package in Ubuntu: New Bug description: Summary: * GDB 10.0 introduced a regression where it cannot inspect any global variables in any D programs compiled by any D compiler. * LDC2 and GDC upstream stated Focal does not have such a problem and stuck to this release for their test images. Reproduce steps: Considering the following D program: ``` module t; class uv { int i; } __gshared uv i; int main() { i = new uv(); return 0; // #break } ``` If you build it using `gdc -g -O0 t.d -o t` or `ldc2 -o t.o t.d -g`, run the GDB using the following commands ... ``` b t.d:10 p t.i ``` ... you will notice GDB will complain that "'t.i' has unknown type; cast it to its declared type." To manage notifications about this bug go to: https://bugs.launchpad.net/gdb/+bug/2059856/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
