On Tue, Apr 8, 2008 at 4:46 PM, Pranav Bhandarkar <[EMAIL PROTECTED]> wrote: > Hi, > > Consider the attached testcase. > > Working on a private port (Infact I see this problem on > arm-none-eabi-gcc too). I see the following in test.c.003t.original > > fail = (short int) usi <= ssi; > > And then in test.c.025t.ssa > usi.2_5 = (short int) usi_4; > fail.3_6 = usi.2_5 <= ssi_2; > > Now ccp1 does constant propagation and we are left with > usi.2_5 = -256; > > This causes the test to fail. > > Clearly the problem seems to be that since usi is unsigned short int a > short int cant represent all the possible values of usi > > I reverted the following patch and the test passed. > PR middle-end/35163 > * fold-const.c (fold_widened_comparison): Use get_unwidened in > value-preserving mode. Disallow final truncation. > > Now with the patch reverted, test.c.003t.original has > > fail = (int) ssi >= (int) usi; > > And this problem vanished. > > > Am I missing something here ?
Please file a bugreport about this. Richard.
