Introduce _Complex conversions into the function overloading
system. Since C99 doesn't have overloading and C++ doesn't have
_Complex, there is no specification for this. Here's what I think
makes sense.
Complex conversions come in several flavors:
- Complex promotions: a complex -> complex conversion where the
underlying real-type conversion is a floating-point promotion. GCC
seems to call this a promotion, EDG does something else. This is
given "promotion" rank for determining the best viable function.
- Complex conversions: a complex -> complex conversion that is
not a complex promotion. This is given "conversion" rank for
determining the best viable function.
- Complex-real conversions: a real -> complex or complex -> real
conversion. This is given "conversion" rank for determining the
best viable function.
These rules are the same for C99 (when using the "overloadable"
attribute) and C++. However, there is one difference in the handling
of floating-point promotions: in C99, float -> long double and double
-> long double are considered promotions (so we give them "promotion"
rank), while C++ considers these conversions ("conversion" rank).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@64343 91177308-0d34-0410-b5e6-96231b3b80d8
6 files changed