std::to_chars is locale-independent, so the ostringstream and imbue(locale)
are no longer needed. Build the REAL string with plain std::string operations.
Output is unchanged (verified in standalone compile: same shortest values, all
round-trip). Addresses review feedback on #8309.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
format_double formatted doubles with setprecision(max_digits10) (17 digits),
which padded clean values with noise: 0.0174532925199433 was rewritten as
0.017453292519943299 and 1.E-05 as 1.0000000000000001E-05. Every REAL in a file
changed on save, producing enormous diffs for anyone version-controlling IFC.
Use std::to_chars, which emits the shortest string that round-trips exactly
(like Python's repr), then keep the existing mantissa/exponent formatting.
Verified in a standalone compile of the exact function logic: the reporter's
values become 0.0174532925199433 and 1.E-05, 0.1 stays 0.1, and every tested
value (including a denormal) round-trips back to the identical double.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
asStringRef removes the first and last characters of a string, enumeration
or binary token to drop the delimiters, guarded only by !str.empty(). A
malformed single-character token (e.g. a bare '.' left when a fuzzer turns
'.PHYSICAL.' into '.)HYSICAL.') has length 1, so the first erase empties the
string and the second erase(str.begin()) runs on an empty string. That is
undefined behaviour: benign on a normal build, but it aborts (or throws
std::length_error from a later append) under a hardened libstdc++ with
_GLIBCXX_ASSERTIONS, which is why this file only segfaulted on the Fedora
build. Require at least two characters before stripping.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
IfcOpenshell read file, and write file without changes. This round trip introduces truncation noise. It should not hurt to increase the precision to keep this clean.
Petru Conduraru