Error: cannot load from non-primitive location in simple struct

Hello,

when having a look at one of my structures in the CCS debugger, I get this error message:  "Error: cannot load from non-primitive location". That's the struct:

// Structure of the FPGA Telegrams
typedef struct FpgaMessageHeader
{
    Float    fSOF;                // Start of Frame = nan
    UInt64  u64Timestamp;

    UInt    u4Channel             : 4; // Please read spru187, section 7.2.2.1 "Generic Bit Fields"
    UInt    u5SampleRateExponent : 5; // before changing the bitfields. Thank you.
    UInt    u7TBD                 : 7; // To be defined / reserved

    UInt16  u16PayloadLength;
} __attribute__((packed)) FpgaMessageHeader_t;   // "packed" is ignored till cl6x 7.2

It instantiated like this:

#pragma DATA_ALIGN( 0x80 )
    static FpgaMessageHeader_t sMessageHeader;

I think it's funny that I can see the bitfields in the debugger, but all the other fields are not displayed.

What's wrong there?

cu

Markus