Fix for speex' autoconfiguration
The attached patch in this ticket fixes three build issues:
- Compile on systems with C99 variable-size arrays that do not support C99 variable declarations. Achieve this by making the check deliberately use C99 variable declarations.
- Add missing check for alloca.h. At least on OpenBSD, alloc() is declared in stdlib.h and alloc.h does not exist. Adjust libspeex/stack_alloc.h to cope.
- Declare 'int tmp;' at the beginning of the code block in libspeex/testecho.c.