Hi,
If ENABLE_BUILD_WITH_CXX is defined, then GCC itself is built with C++,
and we want a C++ signature for functions. If it is not defined, then
GCC itself is not built with C++, and we want (and must have) a C
signature.
I suppose we would decide that fancy_abort always uses a C signature,
but that seems odd.
Ian
I guess the issue is when people care only about C plugins, yet fancy_abort
get implicitly exported with a C++ linkage.
I suspect this goes back to the eternal question: what do we consider as
part of the public GCC public API (no, Basile, I am not suggesting to have
the same discussion again.)
if the following are to hold
(1) fancy_abort is declared in system.h
(2) system.h should not be wrapped in extern "C" when included from a plugin,
(3) it should be valid to include it from plugins compiled as C or as C++,
(4) fancy_abort should use the same linkage as GCC, i.e. C when GCC built as C,
C++ when built as C++ (aka ENABLE_BUILD_WITH_CXX).
then something like the following seems inevitable:
#ifdef ENABLE_BUILD_WITH_CXX
#ifdef __cplusplus
extern void fancy_abort(const char *, int, const char *) ATTRIBUTE_NORETURN;
#else
extern void _Z11fancy_abortPKciS0_(const char *, int, const char *)
ATTRIBUTE_NORETURN;
#endif
#else
#ifdef __cplusplus
extern "C" void fancy_abort(const char *, int, const char *) ATTRIBUTE_NORETURN;
#else
extern void fancy_abort(const char *, int, const char *) ATTRIBUTE_NORETURN;
#endif
#endif
That's pretty nasty. But to avoid the nastiness one of (1) - (4) needs to be
dropped. Which one?
Ciao, Duncan.
