Compilation fix for Ubuntu 24.04, updated docs.

Author: IRainman

include/fast_float/ascii_number.h

@@ -84,6 +84,7 @@ fastfloat_really_inline uint64_t simd_read8_to_u64(__m128i const &data) {
 
 fastfloat_really_inline uint64_t simd_read8_to_u64(char16_t const *chars) {
   FASTFLOAT_SIMD_DISABLE_WARNINGS
+  // unaligned SIMD instruction -> all fine.
   return simd_read8_to_u64(
       _mm_loadu_si128(reinterpret_cast<__m128i const *>(chars)));
   FASTFLOAT_SIMD_RESTORE_WARNINGS
@@ -172,6 +173,7 @@ simd_parse_if_eight_digits_unrolled(char16_t const *chars,
 #ifdef FASTFLOAT_SSE2
   FASTFLOAT_SIMD_DISABLE_WARNINGS
   // Load 8 UTF-16 characters (16 bytes)
+  // unaligned SIMD instruction -> all fine.
   __m128i const data =
       _mm_loadu_si128(reinterpret_cast<__m128i const *>(chars));
   FASTFLOAT_SIMD_RESTORE_WARNINGS

include/fast_float/parse_number.h

@@ -162,7 +162,7 @@ template <> struct from_chars_caller<std::float32_t> {
     // if std::float32_t is defined, and we are in C++23 mode; macro set for
     // float32; set value to float due to equivalence between float and
     // float32_t
-    float val;
+    float val = 0;
     auto ret = from_chars_advanced(first, last, val, options);
     value = val;
     return ret;
@@ -179,7 +179,7 @@ template <> struct from_chars_caller<std::float64_t> {
     // if std::float64_t is defined, and we are in C++23 mode; macro set for
     // float64; set value as double due to equivalence between double and
     // float64_t
-    double val;
+    double val = 0;
     auto ret = from_chars_advanced(first, last, val, options);
     value = val;
     return ret;