[Bug c/99022] New: When ‘long int’ is 32 bits，the conversion between 'vector(2) int' and 'vector(2) long int' can't be done without 'flax-vector-conversions'.

[Bug c/99022] New: When ‘long int’ is 32 bits，the conversion between 'vector(2) int' and 'vector(2) long int' can't be done without 'flax-vector-conversions'.

[gengqi at linux dot alibaba.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99022

            Bug ID: 99022
           Summary: When ‘long int’ is 32 bits，the conversion between
                    'vector(2) int' and 'vector(2) long int' can't be done
                    without 'flax-vector-conversions'.
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gengqi at linux dot alibaba.com
  Target Milestone: ---

Created attachment 50150
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50150&action=edit
riscv64-unknown-linux-gnu-gcc -march=rv32imac -mabi=ilp32 needflax.c -O2 -S

riscv64-unknown-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=/lhome/gengq/riscv64-linux-mastertest/bin/riscv64-unknown-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/lhome/gengq/riscv64-linux-mastertest/libexec/gcc/riscv64-unknown-linux-gnu/11.0.0/lto-wrapper
Target: riscv64-unknown-linux-gnu
Configured with:
/lhome/gengq/riscv-gnu-toolchain-master/riscv-gnu-toolchain/riscv-gcc/configure
--target=riscv64-unknown-linux-gnu
--prefix=/lhome/gengq/riscv64-linux-mastertest
--with-sysroot=/lhome/gengq/riscv64-linux-mastertest/sysroot --with-system-zlib
--enable-shared --enable-tls --enable-languages=c,c++,fortran
--disable-libmudflap --disable-libssp --disable-libquadmath
--disable-libsanitizer --disable-nls --disable-bootstrap --src=.././riscv-gcc
--disable-multilib --with-abi=lp64d --with-arch=rv64gcpxthead
'CFLAGS_FOR_TARGET=-O2   -mcmodel=medlow' 'CXXFLAGS_FOR_TARGET=-O2  
-mcmodel=medlow'
Thread model: posix



riscv64-unknown-linux-gnu-gcc -march=rv32imac -mabi=ilp32 needflax.c -O2 -S
needflax.c: In function 'flax':
needflax.c:6:3: note: use '-flax-vector-conversions' to permit conversions
between vectors with differing element types or numbers of subparts
    6 |   return a;
      |   ^~~~~~
needflax.c:6:10: error: incompatible types when returning type 'int32x2_t' {aka
'__vector(2) int'} but 'lint32x2_t' {aka '__vector(2) long int'} was expected
    6 |   return a;
      |          ^

[Bug c/99022] When ‘long int’ is 32 bits，the conversion between 'vector(2) int' and 'vector(2) long int' can't be done without 'flax-vector-conversions'.

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99022

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|                            |riscv
            Version|unknown                     |11.0

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
This is a known design decision I think.  There's also for sure a duplicate
bugreport somewhere.

[Bug c/99022] When ‘long int’ is 32 bits，the conversion between 'vector(2) int' and 'vector(2) long int' can't be done without 'flax-vector-conversions'.

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99022

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |INVALID
             Status|UNCONFIRMED                 |RESOLVED

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Yes, it is similar as int* and long* cannot be done in normal C code.