> We try to mitigate it with #ifdef guards, #pragma once etc. but in my experience those band-aids don’t solve the problem. Why don't include guards solve the

> We try to mitigate it with #ifdef guards, #pragma once etc. but in my experience those band-aids don’t solve the problem. Why don't include guards solve the problem of duplicate parsing of .h files within one compilation unit? I believe modern compilers can entirely optimize away even the opening and scanning of the file. And even without that, modern NVMe disks are so fast I would imagine the file opens would be negligible. Curious to hear if anyone has data on whether duplicate header file parsing is still an actual performance issue even with modern compilers, modern SSDs, and #pragma once.