Use PRIu32 format specifier when printing time_in_secs

[joseph-yiu]

This patch addresses #35, where a printf statement for time_in_secs() (ee_u32) used the %d format specifier for int. The issue arise when using a 16-bit architecture where %d (int) does not match the size of ee_u32.

2 files are modified:

• core_main.c
• coremark.h (adding inttypes.h)

The change does not affect CoreMark result as it only impact the code for execution time reporting (after the workload is completed).

[petertorelli]

PRIu32, while being C99 compliant, implies 32-bits. Since I don't have any 16-bit systems to test against, I think the worst-case is a warning as the compiler converts. Other than pedantry, there's no impact to the core benchmark timing so this is fine.

[mysterymath]

I took the time to rebuild llvm-mos's copy of coremark without this patch, and we got two warnings. Accordingly, I think there's another place to fix this at line 367.

core_main.c:367:42: warning: format specifies type 'int' but the argument has type 'secs_ret' (aka 'unsigned long') [-Wformat]
  367 |     ee_printf("Total time (secs): %d\n", time_in_secs(total_time));
      |                                   ~~     ^~~~~~~~~~~~~~~~~~~~~~~~
      |                                   %lu
core_main.c:370:19: warning: format specifies type 'int' but the argument has type 'ee_u32' (aka 'unsigned long') [-Wformat]
  369 |         ee_printf("Iterations/Sec   : %d\n",
      |                                       ~~
      |                                       %lu
  370 |                   default_num_contexts * results[0].iterations
      |                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  371 |                       / time_in_secs(total_time));
      |                       ~~~~~~~~~~~~~~~~~~~~~~~~~~
2 warnings generated.

[mysterymath]

I also manually applied this patch along with a similar PRIu32 fix to line 367, and the benchmark passes with no warnings or runtime errors.

[joseph-yiu]

Thanks. I will update that this weekend :)

[joseph-yiu]

Changes merged into development branch (dev_2026q3).