SEGGER Embedded Studio v6.20 compiler warning

Question

Hi DevZone,

I recently updated my version of SEGGER Embedded Studio for ARM to v6.20. Now, warnings that were not shown before are caught.

I want to ignore the warning triggered specifically when giving reference to a member of a packed struct I am getting the following warning:

<taking address of packed member of 'struct <anonymous>' may result in an unaligned pointer value [-Waddress-of-packed-member]>

Example:

typedef struct __attribute__((__packed__))
{
    uint16_t a;                   
    uint16_t b;                   
} ExampleStruct;

void ExampleFunction(uint16_t* var)
{
    // Place data at given pointer address
}

int main(void)
{
    ExampleStruct exampleStruct;

    ExampleFunction(&exampleStruct.a);
    ExampleFunction(&exampleStruct.b);

    return 0;
}

Is it possible to omit certain compiler warnings, or to specify to the compiler that I am doing this intentionally?

user80129 · Accepted Answer

Word is back from SEGGER. 
 Apparently, when using a Nordic license for SEGGER, one has to use the community forums and not the direct support. 
 https://forum.segger.com/ 
 However, I still got a pointer in the right direction from the Engineer who got back to me and was able to figure it out. 
 Solution: 
 
 Go to Project Options -> Code -> Compiler -> Additional C/C++ Compiler Options 
 Make sure to chose the "Common" build configuration if you want this for all build configurations. Alternatively select the specific build configuration of interest. 
 Add the line -Wno-address-of-packed-member 
 Save and rebuild

Also, check out https://gcc.gnu.org/onlinedocs/gcc/Option-Summary.html for more options. 
 
 Hope this helps someone. 
 Br. Casper

SEGGER Embedded Studio v6.20 compiler warning

Top Replies