Fixes UInt64 to Double conversion on ARM64 #865
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Addresses an issue where direct UInt64 to Double conversion, as well as division operations involving UInt64, were failing on 32-bit ARM64 emulation. Implements a workaround by manually converting UInt64 to Double in two parts (hi and lo Cardinal) to avoid the failing operations. This ensures correct parsing of large numbers.
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Pull request overview
This PR fixes a critical bug in Delphi 13's 32-bit RTL affecting Windows ARM64 emulation where UInt64 to Double conversions and division operations fail. The fix implements a workaround by manually converting UInt64 values to Double using a helper function that splits the value into high and low 32-bit components.
- Introduces
U64ToDoublehelper function that safely converts UInt64 to Double by splitting into hi/lo Cardinals - Updates decimal digit parsing in both UTF-8 and Unicode JSON readers to use the new helper
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Addresses an issue where direct UInt64 to Double conversion, as well as division operations involving UInt64, were failing on 32-bit ARM64 emulation.
Implements a workaround by manually converting UInt64 to Double in two parts (hi and lo Cardinal) to avoid the failing operations. This ensures correct parsing of large numbers.
More about the bug in general. It doesn't just affect the delphimvcframework.
https://en.delphipraxis.net/topic/14678-critical-bug-report-delphi-13-32-bit-rtl-failures-on-windows-arm64-emulation