CBOR Writer: Use canonical NaN representation for NaN values #92934
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Tagging subscribers to this area: @dotnet/area-system-security, @bartonjs, @vcsjones Issue DetailsRFC 7049 (CBOR) specifies "If NaN is an allowed value, it must always be represented as 0xf97e00". The only exception I made is when the user explicitly requests precision (FP size) is preserved. The problem occurred for x86, C# defines NaN as 0.0/0.0 which yields -NaN on x86 FP units, which gets encoded as 0xf9fe00. Fixes issue #92080 Also, use positive NaNs on RISC-V for FP ops crossgen-evaluated when host is x86. Part of #84834
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Tagging subscribers to this area: @dotnet/area-system-formats-cbor, @bartonjs, @vcsjones Issue DetailsRFC 7049 (CBOR) specifies "If NaN is an allowed value, it must always be represented as 0xf97e00". The only exception I made is when the user explicitly requests precision (FP size) is preserved. The problem occurred for x86, C# defines NaN as 0.0/0.0 which yields -NaN on x86 FP units, which gets encoded as 0xf9fe00. Fixes issue #92080 Also, use positive NaNs on RISC-V for FP ops crossgen-evaluated when host is x86. Part of #84834
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RFC 7049 (CBOR) specifies "If NaN is an allowed value, it must always be represented as 0xf97e00". The only exception is when the user explicitly requests precision (FP size) is preserved. The problem occurred for x86, C# defines NaN as 0.0/0.0 which yields -NaN on x86 FP units, which gets encoded as 0xf9fe00. Fixes issue dotnet#92080
…t patterns are still readable as NaN.
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NaNs only get written as 4 or 8 bytes only in CTAP2 mode, which requires to preserve all bits anyway. + review fixes
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Originally a race condition exists in `CheckDefaultProvider` and leads to wrong results when many methods are called simultaneously. The PR fixes that by extending the lock statement. Fix dotnet#92934
RFC 7049 (CBOR) specifies "If NaN is an allowed value, it must always be represented as 0xf97e00". The only exception I made is when the user explicitly requests precision (FP size) is preserved.
The problem occurred for x86, C# defines NaN as 0.0/0.0 which yields -NaN on x86 FP units, which gets encoded as 0xf9fe00.
Fixes issue #92080
Also, use positive NaNs on RISC-V for FP ops crossgen-evaluated when host is x86.
Part of #84834
cc @wscho77 @HJLeee @JongHeonChoi @t-mustafin @alpencolt @gbalykov @clamp03 @sirntar @yurai007