Pass the correct architecture to setarch on Linux

Fixes DFHack#1129

CMakeLists.txt

@@ -81,9 +81,11 @@ ENDIF()
 IF("${DFHACK_BUILD_ARCH}" STREQUAL "32")
   SET(DFHACK_BUILD_32 1)
   SET(DFHACK_BUILD_64 0)
+  set(DFHACK_SETARCH "i386")
 ELSEIF("${DFHACK_BUILD_ARCH}" STREQUAL "64")
   SET(DFHACK_BUILD_32 0)
   SET(DFHACK_BUILD_64 1)
+  set(DFHACK_SETARCH "x86_64")
   ADD_DEFINITIONS(-DDFHACK64)
 ELSE()
   MESSAGE(SEND_ERROR "Invalid build architecture (should be 32/64): ${DFHACK_BUILD_ARCH}")
@@ -334,6 +336,9 @@ IF(BUILD_LIBRARY)
     install(FILES LICENSE.rst NEWS.rst DESTINATION ${DFHACK_USERDOC_DESTINATION})
 endif()
 
+file(WRITE "${CMAKE_BINARY_DIR}/dfhack_setarch.txt" ${DFHACK_SETARCH})
+install(FILES "${CMAKE_BINARY_DIR}/dfhack_setarch.txt" DESTINATION "${DFHACK_DATA_DESTINATION}")
+
 install(DIRECTORY dfhack-config/ DESTINATION dfhack-config/default)
 
 #build the plugins

package/linux/dfhack

@@ -63,6 +63,8 @@ export LD_LIBRARY_PATH="./hack/libs:./hack:$LD_LIBRARY_PATH"
 
 PRELOAD_LIB="${PRELOAD_LIB:+$PRELOAD_LIB:}./hack/libdfhack.so"
 
+setarch_arch=$(cat hack/dfhack_setarch.txt || printf i386)
+
 case "$1" in
   -g | --gdb)
     shift
@@ -74,21 +76,21 @@ case "$1" in
     ;;
   -h | --helgrind)
     shift
-    LD_PRELOAD="$PRELOAD_LIB" setarch i386 -R valgrind $DF_HELGRIND_OPTS --tool=helgrind --log-file=helgrind.log ./libs/Dwarf_Fortress "$@"
+    LD_PRELOAD="$PRELOAD_LIB" setarch "$setarch_arch" -R valgrind $DF_HELGRIND_OPTS --tool=helgrind --log-file=helgrind.log ./libs/Dwarf_Fortress "$@"
     ret=$?
     ;;
   -v | --valgrind)
     shift
-    LD_PRELOAD="$PRELOAD_LIB" setarch i386 -R valgrind $DF_VALGRIND_OPTS --log-file=valgrind.log ./libs/Dwarf_Fortress "$@"
+    LD_PRELOAD="$PRELOAD_LIB" setarch "$setarch_arch" -R valgrind $DF_VALGRIND_OPTS --log-file=valgrind.log ./libs/Dwarf_Fortress "$@"
     ret=$?
     ;;
   -c | --callgrind)
     shift
-    LD_PRELOAD="$PRELOAD_LIB" setarch i386 -R valgrind $DF_CALLGRIND_OPTS --tool=callgrind --separate-threads=yes --dump-instr=yes --instr-atstart=no --log-file=callgrind.log ./libs/Dwarf_Fortress "$@"
+    LD_PRELOAD="$PRELOAD_LIB" setarch "$setarch_arch" -R valgrind $DF_CALLGRIND_OPTS --tool=callgrind --separate-threads=yes --dump-instr=yes --instr-atstart=no --log-file=callgrind.log ./libs/Dwarf_Fortress "$@"
     ret=$?
     ;;
   *)
-    setarch i386 -R env LD_PRELOAD="$PRELOAD_LIB" ./libs/Dwarf_Fortress "$@"
+    setarch "$setarch_arch" -R env LD_PRELOAD="$PRELOAD_LIB" ./libs/Dwarf_Fortress "$@"
     ret=$?
     ;;
 esac