Programmatic output of floating point numbers might choose to print
spaces instead of an explicit '+' sign, to align the output with the
result of formatting negative numbers yet achieve a screen appearance
similar to what humans would have written. Skip leading whitespace
before insisting in seeing either signs or digits or decimals.
int32_t exponent = 0;
bool is_negative = false;
+ while (isspace(*str))
+ str++;
+
errno = 0;
integral = g_ascii_strtoll(str, &endptr, 10);