Remove special handling of IN_GCC real_t code.
Don't use long long to cast signed int to float.
Catch gcc ±Inf bugs.
Merge pull request #2276 from ibuclaw/noinfbugs

Catch GCC ±Inf bugs.
Merge pull request #2274 from ibuclaw/realt_ingcc

Remove special handling of IN_GCC real_t code.
Merge pull request #2275 from ibuclaw/nolonglong

Don't use long long to cast signed int to float.