#9689: const_str support needed for hsc2hs in cross-compilation mode -------------------------------------+------------------------------------- Reporter: aosivitz | Owner: Type: feature | Status: new request | Milestone: Priority: normal | Version: 7.8.3 Component: hsc2hs | Keywords: zlib ios cross- Resolution: | compilation Operating System: | Architecture: arm Unknown/Multiple | Difficulty: Unknown Type of failure: Other | Blocked By: Test Case: | Related Tickets: Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Comment (by aosivitz): Digging a little deeper... The reason why const_str is not currently supported is that strings cannot be calculated for a cross-compiled target platform the same way numbers can. Booleans can be calculated by attempting to compile a specific program that uses the boolean value in a static array size. The compiler must calculate the array size to determine if it is non-negative. (A negative array size is a compiler error.) This trick can be extended to numbers repeatedly using them to form boolean expressions and performing a binary search. A const_str is something like #define VERSION "1.2.3" Since a string is just an array of chars, shouldn't we be able to calculate it at compile time as well? We can get the length of a string by testing for -Warray-bounds and -Werror. And then calculate the value of the array at each index. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9689#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler