Parse full-range hex literals with strtoull#1233
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Hex literals like 0xFFFFFFFFFFFFFFFF exceed signed long long; strtoll overflows and errno becomes ERANGE, incorrectly rejecting the literal. Use strtoull and cast to double. Add a regression test for UINT64_MAX.
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As an alternative, in PR #984 I've attempted to create an entirely custom number parsing method. Which, should handle this case, but is certainly a much more aggressive change to the language and handles this a completely different way. It'd consume as many digits that'd fit in the mantissa of a double (about what would fit in 52 bits), consume the rest ignoring the value but incrementing an exponent, then multiplies that mantissa value (as a long double) by the power of the base raised to the exponent. Which should also prevent the overflow as we only parse enough to fit inside of about 52-bits of a 64-bit integer. |
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Summary
Hex integer literals are tokenized as
0x...and parsed with the C library.strtollonly covers the signed range;0xFFFFFFFFFFFFFFFF(UINT64_MAX) overflows, setsERANGE, and the lexer incorrectly reported "Number literal was too large".Use
strtoullso the full 64-bit unsigned range parses, then cast todouble.Regression
test/core/number/hex_literal_uint64_max.wren: fails withstrtoll(compile error), passes withstrtoull.Testing