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Date: Wed, 08 Jul 2009 22:09:00 -0000
Subject: [Bug middle-end/40692]  New: [4.5 Regression] Endless recursion between fold_ternary and fold_cond_expr_with_comparison
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From: "jakub at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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Linux kernel, in particularly xen-blkfront.c, doesn't compile with GCC trunk.
4.5.0 20090625 was still fine, 4.5.0 20090630 is already wrong.

Simplified testcase:

#define M1(x) (((x) & 0x00000002) ? 0x2 : ((x) & 0x1))
#define M2(x) (((x) & 0x0000000c) ? M1 ((x) >> 2) << 2 : M1 (x))
struct A { char f[1]; };
char a[M2 (4096UL - (long)&((struct A *) 16)->f)];


-- 
           Summary: [4.5 Regression] Endless recursion between fold_ternary
                    and fold_cond_expr_with_comparison
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: jakub at gcc dot gnu dot org
        ReportedBy: jakub at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40692