[Clang] Enable warnings on lax vector conversions

[mikolaj-pirog]

This makes clang emit warnings on code that does implicit vector conversions, like so:

__m512 a;
__m512d b;

a = b;

For more, see https://discourse.llvm.org/t/rfc-making-flax-vector-conversions-none-the-default/88008

[github-actions]

⚠️ C/C++ code formatter, clang-format found issues in your code. ⚠️

You can test this locally with the following command:

git-clang-format --diff origin/main HEAD --extensions c,cpp -- clang/lib/Sema/SemaExpr.cpp clang/lib/Sema/SemaOverload.cpp clang/test/AST/ByteCode/builtin-bit-cast.cpp clang/test/CodeGen/AArch64/fp8-intrinsics/acle_neon_fp8_untyped.c clang/test/CodeGen/AArch64/sve-acle-__ARM_FEATURE_SVE_VECTOR_OPERATORS.c clang/test/CodeGen/AArch64/sve-acle-__ARM_FEATURE_SVE_VECTOR_OPERATORS.cpp clang/test/CodeGen/AArch64/targetattr-crypto.c clang/test/CodeGen/LoongArch/lasx/builtin-alias-error.c clang/test/CodeGen/LoongArch/lasx/builtin-error.c clang/test/CodeGen/LoongArch/lsx/builtin-alias-error.c clang/test/CodeGen/LoongArch/lsx/builtin-error.c clang/test/CodeGen/SystemZ/zvector.c clang/test/CodeGen/SystemZ/zvector2.c clang/test/CodeGen/builtins-mips-msa-error.c clang/test/CodeGen/target-builtin-error-3.c clang/test/CodeGen/vector.c clang/test/Sema/aarch64-neon-target.c clang/test/Sema/aarch64-neon-without-target-feature.cpp clang/test/Sema/arm-bfloat.cpp clang/test/Sema/arm-cde-immediates.c clang/test/Sema/arm-mve-immediates.c clang/test/Sema/arm-neon-target.c clang/test/Sema/arm-neon-types.c clang/test/Sema/arm64-neon-header.c clang/test/Sema/attr-arm-sve-vector-bits.c clang/test/Sema/attr-riscv-rvv-vector-bits.c clang/test/Sema/builtins-hvx-none.c clang/test/Sema/builtins-hvx-v60.c clang/test/Sema/builtins-hvx-v62.c clang/test/Sema/builtins-hvx-v65.c clang/test/Sema/builtins-mips-features.c clang/test/Sema/builtins-x86.c clang/test/Sema/constant-builtins-vector.cpp clang/test/Sema/conversion-64-32.c clang/test/Sema/conversion-implicit-int-includes-64-to-32.c clang/test/Sema/ext_vector_ops.c clang/test/Sema/overload-arm-mve.c clang/test/Sema/vector-assign.c clang/test/Sema/vector-cast.c clang/test/Sema/vector-gcc-compat.c clang/test/Sema/vector-gcc-compat.cpp clang/test/Sema/vector-init.c clang/test/Sema/vector-ops.c clang/test/SemaCXX/attr-arm-sve-vector-bits.cpp clang/test/SemaCXX/attr-riscv-rvv-vector-bits.cpp clang/test/SemaCXX/vector.cpp compiler-rt/lib/msan/tests/msan_test.cpp libcxx/test/std/experimental/simd/simd.class/simd_unary.pass.cpp

⚠️
The reproduction instructions above might return results for more than one PR
in a stack if you are using a stacked PR workflow. You can limit the results by
changing origin/main to the base branch/commit you want to compare against.
⚠️

View the diff from clang-format here.

diff --git a/compiler-rt/lib/msan/tests/msan_test.cpp b/compiler-rt/lib/msan/tests/msan_test.cpp
index 99ad2c31a..22a1405af 100644
--- a/compiler-rt/lib/msan/tests/msan_test.cpp
+++ b/compiler-rt/lib/msan/tests/msan_test.cpp
@@ -4132,8 +4132,8 @@ typedef U4 V2x32 __attribute__((__vector_size__(8)));
 typedef U2 V4x16 __attribute__((__vector_size__(8)));
 typedef U1 V8x8 __attribute__((__vector_size__(8)));
 
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecate-lax-vec-conv-all"
+#  pragma clang diagnostic push
+#  pragma clang diagnostic ignored "-Wdeprecate-lax-vec-conv-all"
 
 V8x16 shift_sse2_left_scalar(V8x16 x, U4 y) {
   return _mm_slli_epi16(x, y);
@@ -4349,7 +4349,7 @@ TEST(VectorCmpTest, builtin_ia32_ucomisdlt) {
   EXPECT_NOT_POISONED(c);
 }
 
-#pragma clang diagnostic push
+#  pragma clang diagnostic push
 
 #endif // defined(__x86_64__) && defined(__clang__)