VTDecompressionSessionCreate fails if instantiated with predefined constant from SDK

VTDecompressionSessionCreate fails if instantiated with predefined constant - kVTVideoDecoderSpecification_RequireHardwareAcceleratedVideoDecoder. However it is succeeded if replaced with literal - CFSTR( "RequireHardwareAcceleratedVideoDecoder" ). Literally they have same value. Sample data (sps and pps) identical for both cases.

Could you help please?

Build command:

clang -x objective-c -target x86_64-apple-macos10.14 -framework Foundation -framework CoreMedia -framework VideoToolbox -o vt main.m

VTDecompressionSessionCreate fails if instantiated with predefined constant from SDK
 
 
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