forked from lix-project/lix
0ad643ed5c
Using a 64bit integer on 32bit systems will come with a bit of a performance overhead, but given that Nix doesn't use a lot of integers compared to other types, I think the overhead is negligible also considering that 32bit systems are in decline. The biggest advantage however is that when we use a consistent integer size across all platforms it's less likely that we miss things that we break due to that. One example would be: https://github.com/NixOS/nixpkgs/pull/44233 On Hydra it will evaluate, because the evaluator runs on a 64bit machine, but when evaluating the same on a 32bit machine it will fail, so using 64bit integers should make that consistent. While the change of the type in value.hh is rather easy to do, we have a few more options available for doing the conversion in the lexer: * Via an #ifdef on the architecture and using strtol() or strtoll() accordingly depending on which architecture we are. For the #ifdef we would need another AX_COMPILE_CHECK_SIZEOF in configure.ac. * Using istringstream, which would involve copying the value. * As we're already using boost, lexical_cast might be a good idea. Spoiler: I went for the latter, first of all because lexical_cast does have an overload for const char* and second of all, because it doesn't involve copying around the input string. Also, because istringstream seems to come with a bigger overhead than boost::lexical_cast: https://www.boost.org/doc/libs/release/doc/html/boost_lexical_cast/performance.html The first method (still using strtol/strtoll) also wasn't something I pursued further, because it is also locale-aware which I doubt is what we want, given that the regex for int is [0-9]+. Signed-off-by: aszlig <aszlig@nix.build> Fixes: #2339 |
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| .. | ||
| primops | ||
| attr-path.cc | ||
| attr-path.hh | ||
| attr-set.cc | ||
| attr-set.hh | ||
| common-eval-args.cc | ||
| common-eval-args.hh | ||
| eval-inline.hh | ||
| eval.cc | ||
| eval.hh | ||
| get-drvs.cc | ||
| get-drvs.hh | ||
| json-to-value.cc | ||
| json-to-value.hh | ||
| lexer.l | ||
| local.mk | ||
| names.cc | ||
| names.hh | ||
| nix-expr.pc.in | ||
| nixexpr.cc | ||
| nixexpr.hh | ||
| parser.y | ||
| primops.cc | ||
| primops.hh | ||
| symbol-table.hh | ||
| value-to-json.cc | ||
| value-to-json.hh | ||
| value-to-xml.cc | ||
| value-to-xml.hh | ||
| value.hh | ||