How can I print the result of sizeof() at compile time in C?

Question

How can I print the result of sizeof() at compile time in C?

For now I am using a static assert (home brewed based on other web resources) to compare the sizeof() re

Answer 1

Though this isn't exactly at compile time, it is before runtime, so it could still be relevant for some people.

You can define an array like so:

uint8_t __some_distinct_name[sizeof(YourTypeHere)];

And then, after compilation, get the size from the object file:

$ nm -td -S your_object_file |       # list symbols and their sizes, in decimal
  grep ' __some_distinct_name$' |    # select the right one
  cut -d' ' -f2 |                    # grab the size field
  xargs printf "Your type is %d B\n" # print