ENH: Improve robustness of compiler INFO strings
Compiler INFO strings built at preprocessing time encode information that must appear as a string literal in the resulting binary. We must make sure the strings appear in the final binary no matter what compiler and flags are used. The previous implementation worked in most places but failed with the GNU linker's --gc-sections option which managed to discard the string. Instead we make the program return value depend on an element of the string indexed by a runtime program parameter, which absolutely requires the string to be present.
Showing with 57 additions and 40 deletions