Okay, let's see. The user is reporting an issue where the overflow condition code isn't being determined correctly on s390x when using QEMU. The problem is in the generated code from GCC, which uses the 'o' condition code (overflow) after an addition. The expected behavior is that adding two minimum 32-bit and 64-bit integers should overflow, but QEMU is returning 'no_overflow = 1' instead of 0. The user suggests that the problem might be either in GCC or QEMU. The key part here is that the code generated by GCC uses the CPU's overflow condition code. If QEMU isn't correctly emulating how the overflow condition code is set during operations like 'agr' (Add with Register), then that's a QEMU bug. The user even provided a patch for QEMU that fixes the issue, which points towards QEMU's emulation of the condition codes being incorrect. Since the issue is about how QEMU handles the overflow condition code during instruction execution, this falls under the "instruction" category. The problem isn't with a syscall or runtime environment but with the correct emulation of a specific CPU instruction's side effects (setting the condition code). The patch provided likely corrects how QEMU tracks or checks the overflow condition after arithmetic operations. Therefore, the bug is in QEMU's instruction emulation. instruction