I would have expected that CXXFLAGS="-mno-sse4.1" ./configure would make the sse4.1 intrinsics check fail but it doesn't:
configure:23377: checking for SSE4.1 intrinsics
configure:23396: clang++ -std=c++17 -c -msse4.1 -mno-sse4.1 conftest.cpp >&5
configure:23396: $? = 0
configure:23398: result: yes
Not sure what is going on here, seems like a bug.
Note that this ultimately results in compile failure, but because we try and compile the sha256_x86_shani.cpp code, but fail because it "needs isa option -msse4.1":
In file included from /usr/lib/gcc/x86_64-linux-gnu/13/include/immintrin.h:39,
from crypto/sha256_x86_shani.cpp:12:
In function 'void {anonymous}::Shuffle(__m128i&, __m128i&)',
inlined from 'void sha256_x86_shani::Transform(uint32_t*, const unsigned char*, size_t)' at crypto/sha256_x86_shani.cpp:87:12:
crypto/sha256_x86_shani.cpp:57:10: error: '__builtin_ia32_pblendw128' needs isa option -msse4.1
57 | s1 = _mm_blend_epi16(t2, t1, 0xF0);
| ^~~~~~~~~~~~~~~
In function 'void {anonymous}::Unshuffle(__m128i&, __m128i&)',
inlined from 'void sha256_x86_shani::Transform(uint32_t*, const unsigned char*, size_t)' at crypto/sha256_x86_shani.cpp:138:14:
crypto/sha256_x86_shani.cpp:64:10: error: '__builtin_ia32_pblendw128' needs isa option -msse4.1
64 | s0 = _mm_blend_epi16(t1, t2, 0xF0);
| ^~~~~~~~~~~~~~~
In function 'void {anonymous}::Unshuffle(__m128i&, __m128i&)',
inlined from 'void sha256d64_x86_shani::Transform_2way(unsigned char*, const unsigned char*)' at crypto/sha256_x86_shani.cpp:270:14:
crypto/sha256_x86_shani.cpp:64:10: error: '__builtin_ia32_pblendw128' needs isa option -msse4.1
64 | s0 = _mm_blend_epi16(t1, t2, 0xF0);
| ^~~~~~~~~~~~~~~
In function 'void {anonymous}::Unshuffle(__m128i&, __m128i&)',
inlined from 'void sha256d64_x86_shani::Transform_2way(unsigned char*, const unsigned char*)' at crypto/sha256_x86_shani.cpp:271:14:
crypto/sha256_x86_shani.cpp:64:10: error: '__builtin_ia32_pblendw128' needs isa option -msse4.1
64 | s0 = _mm_blend_epi16(t1, t2, 0xF0);
| ^~~~~~~~~~~~~~~
In function 'void {anonymous}::Unshuffle(__m128i&, __m128i&)',
inlined from 'void sha256d64_x86_shani::Transform_2way(unsigned char*, const unsigned char*)' at crypto/sha256_x86_shani.cpp:348:14:
crypto/sha256_x86_shani.cpp:64:10: error: '__builtin_ia32_pblendw128' needs isa option -msse4.1
64 | s0 = _mm_blend_epi16(t1, t2, 0xF0);
| ^~~~~~~~~~~~~~~
In function 'void {anonymous}::Unshuffle(__m128i&, __m128i&)',
inlined from 'void sha256d64_x86_shani::Transform_2way(unsigned char*, const unsigned char*)' at crypto/sha256_x86_shani.cpp:349:14:
crypto/sha256_x86_shani.cpp:64:10: error: '__builtin_ia32_pblendw128' needs isa option -msse4.1
64 | s0 = _mm_blend_epi16(t1, t2, 0xF0);
| ^~~~~~~~~~~~~~~
make[2]: *** [Makefile:14527: crypto/libbitcoin_crypto_x86_shani_la-sha256_x86_shani.lo] Error 1
and also because we then try and compile the sse4.1 code anyways:
In file included from /usr/lib/gcc/x86_64-linux-gnu/13/include/immintrin.h:37,
from crypto/sha256_sse41.cpp:8:
/usr/lib/gcc/x86_64-linux-gnu/13/include/tmmintrin.h: In function '__m128i sha256d64_sse41::{anonymous}::Read4(const unsigned char*, int)':
/usr/lib/gcc/x86_64-linux-gnu/13/include/tmmintrin.h:136:1: error: inlining failed in call to 'always_inline' '__m128i _mm_shuffle_epi8(__m128i, __m128i)': target specific option mismatch
136 | _mm_shuffle_epi8 (__m128i __X, __m128i __Y)
| ^~~~~~~~~~~~~~~~
crypto/sha256_sse41.cpp:55:28: note: called from here
55 | return _mm_shuffle_epi8(ret, _mm_set_epi32(0x0C0D0E0FUL, 0x08090A0BUL, 0x04050607UL, 0x00010203UL));
| ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-linux-gnu/13/include/tmmintrin.h:136:1: error: inlining failed in call to 'always_inline' '__m128i _mm_shuffle_epi8(__m128i, __m128i)': target specific option mismatch
136 | _mm_shuffle_epi8 (__m128i __X, __m128i __Y)
| ^~~~~~~~~~~~~~~~
crypto/sha256_sse41.cpp:55:28: note: called from here
55 | return _mm_shuffle_epi8(ret, _mm_set_epi32(0x0C0D0E0FUL, 0x08090A0BUL, 0x04050607UL, 0x00010203UL));
| ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
make[2]: *** [Makefile:14520: crypto/libbitcoin_crypto_sse41_la-sha256_sse41.lo] Error 1
Both of these can / should be fixed up.
FWIW, adding -O1 to the test makes it fail with CXXFLAGS="-mno-sse4.1".
This is fixed by #13789 which was inexplicably closed for no reason
It was closed due to #13758 (comment)