Trying to compile Delta firmware to Ceality 4.2.7. Every souce file in comes up as errors

Why does every marlin file come up with errors. I changed config.h and config_adv.h but now every source file comes up with errors -
c:\users\kf2qd\documents\3d printers\marlin-\marlin\src\pins\pins.h:110:9: error: missing binary operator before token “(”
110 | #elif MB(MKS_BASE_15)

this was the first one that showed up -
c:\users\kf2qd\documents\3d printers\marlin-\marlin\src\core\boards.h:504:64: error: operator ‘==’ has no right operand
504 | #define MB_1(B) (defined(BOARD##B) && MOTHERBOARD==BOARD_##B)
I got past that by commenting out those 3 lines. ^
And many more -

What gives. This is the stock marlin code. Shouldn’t it be able to compile?

How exactly or with which files?

Opposite of “I changed config”.

How can we reproduce your problem?

I changed the config.h and config_adv.h inside the Marlin directory. I have done the same previous when compiling under Arduino and it did not break every file like it is under Platformio. Didn’t think what is happening is normal behavior, but maybe I am wrong.

Is there something I don’t see wrong with line 110 in the first example?
is BOARD_##B a bad operand? and if so can someone suggest why?

It’ll be easiest if you upload your complete current marlin project folder so that we can reproduce the error and track down why. Could be anything, like a forgotten or wrongly set macro.