In the early days of compilers, it was expected that programs would generally be stored in an inexpensive medium (such as punched cards or magnetic tape) when not in use. Although it was possible to construct hard-wired read-only memory, very few programs would represent a large enough fraction of a machine's workload to make doing so worthwhile.
By the time of the Apollo Guidance Computer, it was clearly established that there would sometimes be a need for computers which were purpose-built to run one particular program, but the software for the AGC was written in assembly language, rather than in FORTRAN or any other compiled language.
When would a compiler have first been used to generate code which was intended to be permanently built into a computer, or be used to a sufficient degree that having it some hard-wired medium (such as rope memory or electromagnetically-readable punched cards) would be more cost-effective than having it in RAM? Would any special accommodation have been needed to separate things that would be modifiable at run time from things that would not?