I was pointed to: http://david.tribble.com/text/cdiffs.htm#C99-const-linkage which recommends exactly what I'd like to do: >> The recommended practice is therefore to define constants with an explicit static or extern specifier C:\>type 1.c extern const int b = 1; C:\>gcc -c 1.c 1.c:1: warning: `b' initialized and declared `extern' Why the warning? - Jay ---------------------------------------- > From: jay.krell@xxxxxxxxxxx > To: gcc-help@xxxxxxxxxxx > Subject: gcc gets in the way of writing C that is also C++ wrt const > Date: Tue, 21 Jul 2009 11:52:18 +0000 > > > > I try to write C code that is valid C++ and has the same meaning in C++. > > > const int a = 1; > > > does not have the same meaning in C and C++. > > > So I would write: > > > extern const int a = 1; > > > which does have the same meaning in both, but for some reason gcc doesn't quite like this and gives a warning. > > > I end up doing: > > > /* const is extern const in C, but static const in C++, > * but gcc gives a warning for the correct portable form "extern const" */ > #if defined(__cplusplus) || !defined(__GNUC__) > #define EXTERN_CONST extern const > #else > #define EXTERN_CONST const > #endif > > > EXTERN_CONST int a = 1; > > > > which is just lame. > > > - Jay
