Fix ethernet API build warnings for LPC4088

[kegilbert]

LPC4088 ethernet_api build warning fixes to address #5318

Looked like an issue with using a typedef on packed structs in the way it was originally written (https://stackoverflow.com/questions/12213866/is-attribute-packed-ignored-on-a-typedef-declaration).

Does this look reasonable? Tested on a locally exported blinky example for make_armc5. Saw the same warnings as the above issue before moving the PACKED attribute to the end of the struct declaration.

As a quick sanity check I ran the following with and without the PACKED attribute in the struct declaration to confirm the attribute was not silently dropped.

#define MBED_PACKED(struct) struct __attribute__((packed))
#define PACKED MBED_PACKED()

int main(void) {
    struct test {
        unsigned char a;
        unsigned short b;
        unsigned long c;
    } PACKED;

    typedef struct test tTest;

    tTest var1;
    printf("%d\r\n", sizeof(var1));
}

[0xc0170]

LGTM, lets run build only to be certain this is all toolchains compatible

[0xc0170]

/morph build

[0xc0170]

@sarahmarshy review pls

One way to do this also is to use MBED_PACKED that we provide, would that eliminate these warnings?

[mbed-ci]

Build : SUCCESS

Build number : 256
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/5320/

Skipping test trigger, missing label 'NEED CI'

[kegilbert]

Should probably switch to MBED_PACKED actually since it looks like PACKED is older, but it just defines back to MBED_PACKED internally:
https://github.com/ARMmbed/mbed-os/blob/master/platform/mbed_toolchain.h#L375

[adbridge]

@sarahmarshy review pls

BUMP

[sarahmarshy]

LGTM!

[0xc0170]

/morph test

[mbed-ci]

Test : SUCCESS

Build number : 148
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/5320/148

[adbridge]

Should probably switch to MBED_PACKED actually since it looks like PACKED is older, but it just defines back to MBED_PACKED internally:
https://github.com/ARMmbed/mbed-os/blob/master/platform/mbed_toolchain.h#L375

@kegilbert Are you proposing to make a change still on this PR then ?

[kegilbert]

@adbridge I just updated the PR, I was going to gauge if anyone had thoughts on it first. Decided to change it to MBED_PACKED since I'd seen it used a bit more in mbed_toolchain and some filesystem implementations.

[0xc0170]

/morph build

[mbed-ci]

Build : FAILURE

Build number : 348
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/5320/

[studavekar]

Please ignore the failure #5320 (comment) , plugin triggered the build twice.

[mbed-ci]

Build : SUCCESS

Build number : 349
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/5320/

Triggering tests

/morph test
/morph uvisor-test

[mbed-ci]

Test : SUCCESS

Build number : 159
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/5320/159