Hello,

The attached rewrites the "structs" testcase, greatly increasing its 
coverage of struct return inferior function call edge cases.  Of note 
the patch:

- hacks structs.c so that it can be built to test almost any scalar 
struct return construct

- rewrites structs.exp to build structs.c / test structs.c with several 
combinations of char, short, int, long, long long, float, double, and 
long double.

- since the bug that stopped GDB finding inferior function call struct 
return values has been fixed, it expects all tests to pass

Look ok?  Tested on PPC.

Andrew