The retrowatch issue

I have been trying to fix this issue using this link Time.h compiling error - Programming Questions - Arduino Forum
but couldn't :cry: :cry:

the error which i am getting is

Arduino: 1.6.2 (Windows 8.1), Board: "Arduino Pro or Pro Mini, ATmega328 (5V, 16 MHz)"

In file included from RetroWatchArduino_u8glib_spi.ino:34:0:

bitmap.h:1269:43: error: variable 'bitmap_array' must be const in order to be put into read-only section by means of 'attribute((progmem))'

PROGMEM const unsigned char* bitmap_array[] = {

^

RetroWatchArduino_u8glib_spi.ino:125:32: error: variable 'weekString' must be const in order to be put into read-only section by means of 'attribute((progmem))'

RetroWatchArduino_u8glib_spi.ino:126:32: error: variable 'ampmString' must be const in order to be put into read-only section by means of 'attribute((progmem))'

RetroWatchArduino_u8glib_spi.ino:163:30: error: variable 'strIntro' must be const in order to be put into read-only section by means of 'attribute((progmem))'

Error compiling.

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plz help!!

the code was obtained from the following link

Change the offending lines to:

PROGMEM const unsigned char* const bitmap_array[] = {
PROGMEM const char* const weekString[] = {"", "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};
PROGMEM const char* const ampmString[] = {"AM", "PM"};
PROGMEM const char* const strIntro[] = {"Retro", "Watch", "Arduino v1.0"};

The first 'const' says that the char pointers point to 'const' characters. The second 'const' says that the array of pointers is, itself, 'const' so it is safe to put the array in PROGMEM.