In article <29********************************@4ax.com>,
C. J. Clegg <re****************@nospam.no> wrote:
A month or so ago I read a discussion about putting const ints in
header files, and how one shouldn't put things in header files that
allocate memory, etc. because they will generate multiple definition
errors if the header file is #include'd in more than one code file.
The answer was that constants have internal linkage unless declared
extern, so it's OK.
So, you can put something like...
const int abc = 123;
... in a header file and be fine (in C++, not in C).
I have run into a related problem.
In one of my header files I have:
const int maxLen = 128;
const char* theMsg = "Hello, world";
Try this:
const char* const theMsg = "Hello, world";
See if that gets rid of the errors.
This header file is #include'd in about eleventy-gazillion places
throughout the system.
When I compile, the compilerand linker is perfectly happy with the
const int, but generates a slew of "multiple definition" errors at
link time for the const char*.
What's the difference between const int and const char* that would
make one work and the other not?
The difference is that "const int" is const, whereas "const char*" is
mutable (even if that to which it points is not.)
--
Magic depends on tradition and belief. It does not welcome observation,
nor does it profit by experiment. On the other hand, science is based
on experience; it is open to correction by observation and experiment.