On Tue, May 10, 2011 at 12:08 PM, fanqifei <fanqi...@gmail.com> wrote: > Hi all, > > I am poring gcc 4.3.2 for a micro-controller and use it to compile C > source code. > I found that gcc is very sensitive to small changes in C source code > even if the change doesn't affect any function of the source code. > For example, a source file foo.c includes a header file foo.h. > If one macro definition is added to foo.h and the macro is not used in > foo.c. The assembly file foo.s is still changed and a few instructions > swapped positions . > I checked foo.c.129t.final_cleanup and found difference in it. > > I am wondering what caused the change in foo.o. Is there any > randomization in gcc? > How can I make the assembly file foo.s same no matter foo.h is changed or not?
alias analysis behavior depends on DECL_UIDs for partitioning which unfortunately shows this behavior in older releases (fixed as of GCC 4.5 at least). Richard. > Thanks > -Qifei Fan >
