I ran Software Update on my Fedora 13 system, and now whenever I build U-Boot, I get a bunch of warnings like this:

dlmalloc.c: In function 'malloc': dlmalloc.c:2252: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules dlmalloc.c:2252: note: initialized from here dlmalloc.c:2261: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules dlmalloc.c:2261: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules dlmalloc.c:2261: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules dlmalloc.c:2261: note: initialized from here dlmalloc.c:2268: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules dlmalloc.c:2268: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules dlmalloc.c:2268: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules dlmalloc.c:2268: note: initialized from here dlmalloc.c:2325: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules dlmalloc.c:2325: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules dlmalloc.c:2325: warning: dereferencing pointer '({anonymous})' does break strict-aliasing rules dlmalloc.c:2325: note: initialized from here

Can anyone explain why this is happening? I don't understand how a Fedora update would change anything, since my cross-compile toolchain is not distributed with Fedora, so it shouldn't have changed.