Merge branch 'main' of github.com:fastfloat/fast_float

Author: lemire

README.md

@@ -66,7 +66,7 @@ The library seeks to follow the C++17 (see [20.19.3](http://eel.is/c++draft/char
 Furthermore, we have the following restrictions:
 * We only support `float` and `double` types at this time.
 * We only support the decimal format: we do not support hexadecimal strings.
-* For values that are either very large or very small (e.g., `1e9999`), we represent it using the infinity or negative infinity value.
+* For values that are either very large or very small (e.g., `1e9999`), we represent it using the infinity or negative infinity value and the returned `ec` is set to `std::errc::result_out_of_range`.
 
 We support Visual Studio, macOS, Linux, freeBSD. We support big and little endian. We support 32-bit and 64-bit systems.
 

include/fast_float/parse_number.h

@@ -214,6 +214,10 @@ from_chars_result from_chars_advanced(const char *first, const char *last,
   // then we need to go the long way around again. This is very uncommon.
   if(am.power2 < 0) { am = digit_comp<T>(pns, am); }
   to_float(pns.negative, am, value);
+  // Test for over/underflow.
+  if ((pns.mantissa != 0 && am.mantissa == 0 && am.power2 == 0) || am.power2 == binary_format<T>::infinite_power()) {
+    answer.ec = std::errc::result_out_of_range;
+  }
   return answer;
 }