I will oppose.

• In 32-bit mode kernel space, 32-bit integers are insufficient (in personal terms, I'm glad if I can handle unsigned integer with more than 64 bits...).

  If you define MRB_WITHOUT_FLOAT, the restriction is more strong.

• gembox "full-core" succeeds even if mrb_int type included in struct RArray or struct RString is replaced with intptr_t (currently mruby-complex and mruby-rational requires modification).

  I do not think that there is a problem because it can not be longer than 32 bits length in 32-bit mode (it would be a bug if there were any).

Thank you for your comment.

Then, as you say, mrb_int size will be allowed to exceed pointer size and type for sizes such as string length it may be better to limit to pointer size (introduce a new type, e.g. mrb_size, which is an alias for intptr_t or uintptr_t?).

Or, it may be possible to limit mrb_int size to pointer size and introduce a type for Fixnum that be allowed to exceed pointer size (e.g. mrb_fixnum).

There is no objection to the introduction of mrb_size and a change of type.

I think that it is better to leave the definition of mrb_int as it is from the viewpoint of the compatibility so far.

I checked what kind of transition the type of the len field of struct RString has followed:

• Initially it was size_t:
  https://github.com/mruby/mruby/blame/2fc1b8af2db70e2e008cecb9fd2d8600034f95f9/include/mruby/string.h#L29
• It became long:
  2970b6a#diff-d1ee00f2602251e1778ccf96047654c7L29
• It became int:
  f4cf8ea#diff-d1ee00f2602251e1778ccf96047654c7L29
• It has now become the current mrb_int:
  7e910bd#diff-d1ee00f2602251e1778ccf96047654c7L32
• Release mruby-1.0.0.

Other object structures that exceed 6 words in 32-bit mode are struct RBreak defined in include/mruby/error.h.

If we define MRB_USE_FLOAT, it will be 6 words length.

• print object size:

  % cc -m32 -Iinclude -o sizeof sizeof.c && ./sizeof
  size of struct RBreak: 28
  % cc -m32 -Iinclude -DMRB_USE_FLOAT -o sizeof sizeof.c && ./sizeof
  size of struct RBreak: 24
  

• cat sizeof.c

  #include <mruby.h>
  #include <mruby/error.h>
  #include <stdio.h>
  
  int
  main(int argc, char *argv[])
  {
    printf("size of struct RBreak: %zd\n", sizeof(struct RBreak));
    return 0;
  }

Thank you for your investigation.

I think another fix is necessary for RBreak, so it might be better to create another ticket.

I close this PR because it has been resolved via #4662 and #4835.