I've inherited some code which has const std::string values defined in
a header file, like
const std::string str = "foo";
This causes a large amount of bloat, as all the compilation units
including this header file will have a copy of the string, as well as
code to construct and destruct the string, even if the string is not
used within the CPP file.
I cannot use the straight-forward solution of converting the 'const' to
'extern const' because this would involve adding a new library, which
is not possible at this point.
The only solution I can think of which will avoid most of the bloat is
to change the definition to:
inline const std::string &get_const_str( ) { static const std::string s
= "foo"; return s; }
But this would mean turning the const variable to a function. I would
really appreciate any suggestions on how to get a similar effect
without converting the constants to functions, any GCC specific trick
will do too...
Thanks,
JC. 1 4607
* C. Jayachandran: I've inherited some code which has const std::string values defined in a header file, like
const std::string str = "foo";
This causes a large amount of bloat, as all the compilation units including this header file will have a copy of the string, as well as code to construct and destruct the string, even if the string is not used within the CPP file.
I cannot use the straight-forward solution of converting the 'const' to 'extern const' because this would involve adding a new library, which is not possible at this point.
The only solution I can think of which will avoid most of the bloat is to change the definition to:
inline const std::string &get_const_str( ) { static const std::string s = "foo"; return s; }
But this would mean turning the const variable to a function. I would really appreciate any suggestions on how to get a similar effect without converting the constants to functions, any GCC specific trick will do too...
The first you should do is _measure_ whether it actually makes a
difference.
If it really really matters, then you can use the template constant
trick (patent pending... ;-) ),
template< typename T >
struct Strings_{ static const std::string str; };
template< typename T >
std::string const Strings_<T>::st r = "foo";
typedef Strings_<void> Strings;
int main()
{
std::cout << Strings::str << std::endl;
}
Hth.
--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail? This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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