* ./ipkg/Makefile.in: removed a file handled by automake.
* ./configure.ac.in: additional warning flags for GCC.
-Wconversion
Warn if a prototype causes a type conversion that is different from
what would happen to the same argument in the absence of a proto-
type.
-Wsign-compare
Warn when a comparison between signed and unsigned values could
produce an incorrect result when the signed value is converted to
unsigned.
-Wunreachable-code
Warn if the compiler detects that code will never be executed.
-Wdisabled-optimization
Warn if a requested optimization pass is disabled.
See the gcc documentation for more explanations. This triggers a lot of
warnings everywhere, and at first sight they're all worth fixing. Code
quality matters, too, so let's fix'em :)