-Wasm-operand-widths when building 4.2.0 for ARM64 Windows (+ ASM bignum seems broken) #1210
Description
Example:
-- The C compiler identification is Clang 21.1.4
-- The ASM compiler identification is Clang with GNU-like command-line
-- Found assembler: /home/appveyor/projects/curl-for-win/llvm-mingw/bin/clang
[...]
[107/508] Building C object crypto/CMakeFiles/crypto_obj.dir/bn/bn_add.c.obj
In file included from /home/appveyor/projects/curl-for-win/libressl/crypto/bn/bn_add.c:63:
/home/appveyor/projects/curl-for-win/libressl/crypto/bn/arch/aarch64/bn_arch.h:35:16: warning: value size does not match register size specified by the constraint and modifier [-Wasm-operand-widths]
35 | : [n]"=r"(n)
| ^
/home/appveyor/projects/curl-for-win/libressl/crypto/bn/arch/aarch64/bn_arch.h:34:18: note: use constraint modifier "w"
34 | __asm__ ("clz %[n], %[w]"
| ^~~~
| %w[n]
/home/appveyor/projects/curl-for-win/libressl/crypto/bn/arch/aarch64/bn_arch.h:36:15: warning: value size does not match register size specified by the constraint and modifier [-Wasm-operand-widths]
36 | : [w]"r"(w));
| ^
/home/appveyor/projects/curl-for-win/libressl/crypto/bn/arch/aarch64/bn_arch.h:34:24: note: use constraint modifier "w"
34 | __asm__ ("clz %[n], %[w]"
| ^~~~
| %w[w]
[...]
2365 of them appear in total.
Minimal reproducer with CMake:
cmake -B _bld \
-DBUILD_SHARED_LIBS=OFF -DLIBRESSL_APPS=OFF -DLIBRESSL_TESTS=OFF \
-DCMAKE_SYSTEM_NAME=Windows -DCMAKE_SYSTEM_PROCESSOR=aarch64 \
-DCMAKE_C_COMPILER_TARGET=aarch64-w64-mingw32 \
-DCMAKE_C_COMPILER=/path/to/llvm-mingw/bin/clangThe toolchain used is llvm-mingw:
https://github.com/mstorsjo/llvm-mingw/releases/tag/20251021
Complete live log:
https://ci.appveyor.com/project/curlorg/curl-for-win/builds/52968287
https://ci.appveyor.com/api/buildjobs/whw97v32kq69hj67/log
Full compiler command-line:
[112/508] /path/to/llvm-mingw/bin/clang --target=aarch64-w64-mingw32 -DHAVE_ASPRINTF
-DHAVE_FTRUNCATE -DHAVE_GETOPT -DHAVE_STRCASECMP -DHAVE_STRNLEN
-DLIBRESSL_CRYPTO_INTERNAL -DLIBRESSL_INTERNAL -DNO_SYSLOG
-DOPENSSLDIR=\"C:/Windows/libressl/ssl\" -DOPENSSL_NO_HW_PADLOCK
-DWIN32_LEAN_AND_MEAN -D_CRT_DEPRECATED_NO_WARNINGS -D_CRT_SECURE_NO_WARNINGS
-D_GNU_SOURCE -D_POSIX -D_POSIX_SOURCE -D_POSIX_THREAD_SAFE_FUNCTIONS
-D_REENTRANT -D_WIN32_WINNT=0x0600 -D__BEGIN_HIDDEN_DECLS=""
-D__END_HIDDEN_DECLS="" -D__USE_MINGW_ANSI_STDIO
-I/path/to/libressl-4.2.0/crypto/. -I/path/to/libressl-4.2.0/crypto/aes -I/path/to/libressl-4.2.0/crypto/asn1
-I/path/to/libressl-4.2.0/crypto/bio -I/path/to/libressl-4.2.0/crypto/bn -I/path/to/libressl-4.2.0/crypto/bytestring
-I/path/to/libressl-4.2.0/crypto/conf -I/path/to/libressl-4.2.0/crypto/dh -I/path/to/libressl-4.2.0/crypto/dsa
-I/path/to/libressl-4.2.0/crypto/curve25519 -I/path/to/libressl-4.2.0/crypto/ec -I/path/to/libressl-4.2.0/crypto/ecdh
-I/path/to/libressl-4.2.0/crypto/ecdsa -I/path/to/libressl-4.2.0/crypto/err -I/path/to/libressl-4.2.0/crypto/evp
-I/path/to/libressl-4.2.0/crypto/hidden -I/path/to/libressl-4.2.0/crypto/hmac -I/path/to/libressl-4.2.0/crypto/lhash
-I/path/to/libressl-4.2.0/crypto/mlkem -I/path/to/libressl-4.2.0/crypto/modes -I/path/to/libressl-4.2.0/crypto/ocsp
-I/path/to/libressl-4.2.0/crypto/pkcs12 -I/path/to/libressl-4.2.0/crypto/rsa -I/path/to/libressl-4.2.0/crypto/sha
-I/path/to/libressl-4.2.0/crypto/stack -I/path/to/libressl-4.2.0/crypto/x509 -I/path/to/libressl-4.2.0/crypto/../include/compat
-I/path/to/libressl-4.2.0/crypto/../include -I/path/to/libressl-4.2.0/_cm-bld-llvm-mingw-libressl-1210/include
-I/path/to/libressl-4.2.0/crypto/arch/aarch64 -I/path/to/libressl-4.2.0/crypto/bn/arch/aarch64
-Wall -O3 -Wno-pointer-sign -MD -MT crypto/CMakeFiles/crypto_obj.dir/bn/bn_add.c.obj
-MF crypto/CMakeFiles/crypto_obj.dir/bn/bn_add.c.obj.d -o crypto/CMakeFiles/crypto_obj.dir/bn/bn_add.c.obj
-c /path/to/libressl-4.2.0/crypto/bn/bn_add.c