Hello, > fstat(3, 0xffad5874) = -1 EOVERFLOW (Value too large for defined data type) > fstat64(3, {st_mode=S_IFDIR|0555, st_size=4096, ...}) = 0 > fstat64(3, {st_mode=S_IFDIR|0555, st_size=4096, ...}) = 0 > > So I think somehow, bootstrap packages use the legacy "fstat" syscall, > which may overflow on a 64 bits system. More info on that one. Linux syscall "newstat", will call "cp_compat_stat". This function starts by checking the device id: --8<---------------cut here---------------start------------->8--- struct compat_stat tmp; if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev)) return -EOVERFLOW; --8<---------------cut here---------------end--------------->8--- Here, stat->dev is 66308 (major: 259, minor 4). "old_valid_dev" checks that: --8<---------------cut here---------------start------------->8--- static inline bool old_valid_dev(dev_t dev) { return MAJOR(dev) < 256 && MINOR(dev) < 256; }--8<---------------cut here---------------end--------------->8--- Which is false here, because my NVME disk has a BLOCK_EXT_MAJOR (259). So stat, lstat, and all other related function will return -EOVERFLOW unless their 64 bits stat64, lstat64 counterpart is used. So I think this means that one cannot build the Guix bootstrap toolchain on an NVME disk. Thanks, Mathieu