[Bug c/86727] New: Struct argument in xmm0 register instead of rcx on Win64

[bart at bartjanssens dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86727

Bug ID: 86727
   Summary: Struct argument in xmm0 register instead of rcx on
Win64
   Product: gcc
   Version: 8.2.0
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: c
  Assignee: unassigned at gcc dot gnu.org
  Reporter: bart at bartjanssens dot org
  Target Milestone: ---

Created attachment 44462
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44462&action=edit
Test case

When passing a struct containing a single value of type double, the argument is
fetched from the %xmm0 register, where the %rcx register should actually be
used on 64 bit Windows. Both mingw GCC 6.4.0 and 8.2.0 read the argument like
this:

movsd   %xmm0, 16(%rbp)

Clang and MSVC both read correctly from %rcx.

Attached is a self-contained example, assembly dumped with

x86_64-w64-mingw32-gcc -S -o - -x c test.c

shows the problem. More discussion is also at:
https://github.com/JuliaLang/julia/issues/28325

When changing the field type to e.g. int or when adding extra fields to the
struct the problem goes away.

[Bug target/64243] Passing and returning structures with single member of floating type via SSE registers is wrong on Windows x86-64 ABI

[bart at bartjanssens dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64243

--- Comment #2 from Bart Janssens  ---
Any chance that this can be upgraded to "confirmed"? Seems this has been around
for a while...

[Bug target/64243] Passing and returning structures with single member of floating type via SSE registers is wrong on Windows x86-64 ABI

[bart at bartjanssens dot org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64243

Bart Janssens  changed:

   What|Removed |Added

 CC||bart at bartjanssens dot org

--- Comment #3 from Bart Janssens  ---
We are still having this issue, it now manifests in cross-compiled binaries
used in the Julia ecosystem, see:
https://github.com/JuliaPackaging/BinaryBuilder.jl/issues/315

[Bug target/64243] Passing and returning structures with single member of floating type via SSE registers is wrong on Windows x86-64 ABI

[bart at bartjanssens dot org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64243

--- Comment #7 from Bart Janssens  ---
Thanks, confirmed that this is also working on GCC 10.2. Unfortunately the
latest in our compiler images is 9.1, and that seems to be still affected, so
we'll have to upgrade.

[Bug c++/105779] New: internal_error on passing a pointer to static function to another function

[bart at bartjanssens dot org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105779

Bug ID: 105779
   Summary: internal_error on passing a pointer to static function
to another function
   Product: gcc
   Version: 12.1.0
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: c++
  Assignee: unassigned at gcc dot gnu.org
  Reporter: bart at bartjanssens dot org
  Target Milestone: ---

Created attachment 53054
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53054&action=edit
Minimal example to reproduce this

Compiling the attached test case fails, explicitly adding & on line 23 to
indicate that method takes a pointer to a function solves the problem, but I
believe both should compile (and did prior to GCC 12), and certainly not crash.

Compile command: g++ -Wall -Wextra test-pointer.cpp
Output:
during RTL pass: expand
test-pointer.cpp: In member function ‘int
WrapSmartPointer::operator()(TypeWrapperT&&) [with TypeWrapperT = IntWrapper]’:
test-pointer.cpp:23:18: internal compiler error: Segmentation fault
   23 | return method(DereferenceSmartPointer::apply); //
method(&DereferenceSmartPointer::apply) works
  |~~^~
0x1ac4724 internal_error(char const*, ...)
???:0
0x11072d7 make_decl_rtl(tree_node*)
???:0
0x95ad77 expand_call(tree_node*, rtx_def*, int)
???:0
0xab27af expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
???:0
0xa930b4 store_expr(tree_node*, rtx_def*, int, bool, bool)
???:0
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://bugs.archlinux.org/> for instructions.

GCC version: g++ (GCC) 12.1.0 (Arch Linux package)
System: Linux 5.15.43-1-lts #1 SMP Wed, 25 May 2022 14:08:34 + x86_64
GNU/Linux