On Fri, Nov 20, 2020 at 12:34 AM Kito Cheng <kito.ch...@sifive.com> wrote:
> - Define MULTILIB_DEFAULTS can reduce the total number of multilib if > the default arch and ABI are listed in the multilib config. > It looks like a good idea, but it doesn't seem to work. A toolchain configured without specifying arch/abi gives me rohan:2149$ riscv64-unknown-elf-gcc --print-multi-lib .; rv32i/ilp32;@march=rv32i@mabi=ilp32 rv32im/ilp32;@march=rv32im@mabi=ilp32 rv32iac/ilp32;@march=rv32iac@mabi=ilp32 rv32imac/ilp32;@march=rv32imac@mabi=ilp32 rv32imafc/ilp32f;@march=rv32imafc@mabi=ilp32f rv64imac/lp64;@march=rv64imac@mabi=lp64 rv64imafdc/lp64d;@march=rv64imafdc@mabi=lp64d The rv64imafdc/lp64d is actually built twice, as it is the default and is built explicitly. But otherwise the list is correct. If I configure a toolchain with the patch using --with-arch=rv32i --with-abi=ilp32 --enable-multilib then I get rohan:2151$ ./xgcc -B./ --print-multi-lib .; rv32imafc/ilp32f;@march=rv32imafc@mabi=ilp32f rv64imac/lp64;@march=rv64imac@mabi=lp64 rv64imafdc/lp64d;@march=rv64imafdc@mabi=lp64d and notice that 3 multilibs have mysteriously disappeared. We have four multilibs with -mabi=ilp32. The rv32i/ilp32 multilib is gone as it is now the default, but the other 3 should still be there. The gcc/multilib.h file in the gcc build dir looks correct. I think that there is something wrong with the processing of the default args against the multilib list. if you have just one default arg, and an entry matches then obviously you don't build it. But if you have two default args, then both must match before you choose to not build it, and I think the code has never supported this case. This works for the --with-multilib-list case because we currently only support one arch/abi with this configure option, so there can be no confusion with matching multiple default arguments. Jim
