The function simplify_binary_operation_1 has code that does /* Convert (compare (gt (flags) 0) (lt (flags) 0)) to (flags). */ but this transformation is only valid if "flags" has the same machine mode as the outer compare. This fixes it. PR rtl-optimization/60818 * simplify-rtx.c (simplify_binary_operation_1): Do not replace a compare of comparisons with the thing compared if this results in a different machine mode. gcc/testsuite/ PR rtl-optimization/60818 * gcc.c-torture/compile/pr60818.c: New testcase. From-SVN: r246666