Hi Linus,

The following changes since commit c2f2b01b74be8b40a2173372bcd770723f87e7b2:

Merge tag 'i3c/for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux (2025-12-08 11:25:14 +0900)

are available in the Git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/hpa/linux-auto.git

for you to fetch changes up to branch auto-type-for-6.19 (4ecc26fa585216f98d71411ce182f9e823d94c8c):

tools/virtio: replace "__auto_type" with "auto" (2025-12-08 15:32:15 -0800)

---------------------------------------------------------------- H. Peter Anvin (7): compiler_types.h: add "auto" as a macro for "__auto_type" include/linux: change "__auto_type" to "auto" fs/proc: replace "__auto_type" with "const auto" arch/nios2: replace "__auto_type" and adjacent equivalent with "auto" arch/x86: replace "__auto_type" with "auto" selftests/bpf: replace "__auto_type" with "auto" tools/virtio: replace "__auto_type" with "auto"

arch/nios2/include/asm/uaccess.h | 8 ++++---- arch/x86/include/asm/bug.h | 2 +- arch/x86/include/asm/string_64.h | 6 +++--- arch/x86/include/asm/uaccess_64.h | 2 +- fs/proc/inode.c | 19 +++++++++---------- include/linux/cleanup.h | 6 +++--- include/linux/compiler.h | 2 +- include/linux/compiler_types.h | 13 +++++++++++++ include/linux/minmax.h | 6 +++--- .../testing/selftests/bpf/prog_tests/socket_helpers.h | 9 +++++++-- tools/virtio/linux/compiler.h | 2 +- 11 files changed, 46 insertions(+), 29 deletions(-)

diff --git a/arch/nios2/include/asm/uaccess.h b/arch/nios2/include/asm/uaccess.h index b8299082adbe..6ccc9a232c23 100644 --- a/arch/nios2/include/asm/uaccess.h +++ b/arch/nios2/include/asm/uaccess.h @@ -172,15 +172,15 @@ do { \

#define __put_user(x, ptr) \ ({ \ - __auto_type __pu_ptr = (ptr); \ - typeof(*__pu_ptr) __pu_val = (typeof(*__pu_ptr))(x); \ + auto __pu_ptr = (ptr); \ + auto __pu_val = (typeof(*__pu_ptr))(x); \ __put_user_common(__pu_val, __pu_ptr); \ })

#define put_user(x, ptr) \ ({ \ - __auto_type __pu_ptr = (ptr); \ - typeof(*__pu_ptr) __pu_val = (typeof(*__pu_ptr))(x); \ + auto __pu_ptr = (ptr); \ + auto __pu_val = (typeof(*__pu_ptr))(x); \ access_ok(__pu_ptr, sizeof(*__pu_ptr)) ? \ __put_user_common(__pu_val, __pu_ptr) : \ -EFAULT; \ diff --git a/arch/x86/include/asm/bug.h b/arch/x86/include/asm/bug.h index ee23b98353d7..d561a8443c13 100644 --- a/arch/x86/include/asm/bug.h +++ b/arch/x86/include/asm/bug.h @@ -129,7 +129,7 @@ do { \

#define __WARN_FLAGS(cond_str, flags) \ do { \ - __auto_type __flags = BUGFLAG_WARNING|(flags); \ + auto __flags = BUGFLAG_WARNING|(flags); \ instrumentation_begin(); \ _BUG_FLAGS(cond_str, ASM_UD2, __flags, ARCH_WARN_REACHABLE); \ instrumentation_end(); \ diff --git a/arch/x86/include/asm/string_64.h b/arch/x86/include/asm/string_64.h index 79e9695dc13e..4635616863f5 100644 --- a/arch/x86/include/asm/string_64.h +++ b/arch/x86/include/asm/string_64.h @@ -31,7 +31,7 @@ KCFI_REFERENCE(__memset); #define __HAVE_ARCH_MEMSET16 static inline void *memset16(uint16_t *s, uint16_t v, size_t n) { - const __auto_type s0 = s; + const auto s0 = s; asm volatile ( "rep stosw" : "+D" (s), "+c" (n) @@ -44,7 +44,7 @@ static inline void *memset16(uint16_t *s, uint16_t v, size_t n) #define __HAVE_ARCH_MEMSET32 static inline void *memset32(uint32_t *s, uint32_t v, size_t n) { - const __auto_type s0 = s; + const auto s0 = s; asm volatile ( "rep stosl" : "+D" (s), "+c" (n) @@ -57,7 +57,7 @@ static inline void *memset32(uint32_t *s, uint32_t v, size_t n) #define __HAVE_ARCH_MEMSET64 static inline void *memset64(uint64_t *s, uint64_t v, size_t n) { - const __auto_type s0 = s; + const auto s0 = s; asm volatile ( "rep stosq" : "+D" (s), "+c" (n) diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h index 641f45c22f9d..915124011c27 100644 --- a/arch/x86/include/asm/uaccess_64.h +++ b/arch/x86/include/asm/uaccess_64.h @@ -72,7 +72,7 @@ static inline void __user *mask_user_address(const void __user *ptr) return ret; } #define masked_user_access_begin(x) ({ \ - __auto_type __masked_ptr = (x); \ + auto __masked_ptr = (x); \ __masked_ptr = mask_user_address(__masked_ptr); \ __uaccess_begin(); __masked_ptr; })

diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 2d3425cfa94b..b7634f975d98 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -303,7 +303,7 @@ static ssize_t proc_reg_read_iter(struct kiocb *iocb, struct iov_iter *iter)

static ssize_t pde_read(struct proc_dir_entry *pde, struct file *file, char __user *buf, size_t count, loff_t *ppos) { - __auto_type read = pde->proc_ops->proc_read; + const auto read = pde->proc_ops->proc_read; if (read) return read(file, buf, count, ppos); return -EIO; @@ -325,7 +325,7 @@ static ssize_t proc_reg_read(struct file *file, char __user *buf, size_t count,

static ssize_t pde_write(struct proc_dir_entry *pde, struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - __auto_type write = pde->proc_ops->proc_write; + const auto write = pde->proc_ops->proc_write; if (write) return write(file, buf, count, ppos); return -EIO; @@ -347,7 +347,7 @@ static ssize_t proc_reg_write(struct file *file, const char __user *buf, size_t

static __poll_t pde_poll(struct proc_dir_entry *pde, struct file *file, struct poll_table_struct *pts) { - __auto_type poll = pde->proc_ops->proc_poll; + const auto poll = pde->proc_ops->proc_poll; if (poll) return poll(file, pts); return DEFAULT_POLLMASK; @@ -369,7 +369,7 @@ static __poll_t proc_reg_poll(struct file *file, struct poll_table_struct *pts)

static long pde_ioctl(struct proc_dir_entry *pde, struct file *file, unsigned int cmd, unsigned long arg) { - __auto_type ioctl = pde->proc_ops->proc_ioctl; + const auto ioctl = pde->proc_ops->proc_ioctl; if (ioctl) return ioctl(file, cmd, arg); return -ENOTTY; @@ -392,7 +392,7 @@ static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigne #ifdef CONFIG_COMPAT static long pde_compat_ioctl(struct proc_dir_entry *pde, struct file *file, unsigned int cmd, unsigned long arg) { - __auto_type compat_ioctl = pde->proc_ops->proc_compat_ioctl; + const auto compat_ioctl = pde->proc_ops->proc_compat_ioctl; if (compat_ioctl) return compat_ioctl(file, cmd, arg); return -ENOTTY; @@ -414,7 +414,7 @@ static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned

static int pde_mmap(struct proc_dir_entry *pde, struct file *file, struct vm_area_struct *vma) { - __auto_type mmap = pde->proc_ops->proc_mmap; + const auto mmap = pde->proc_ops->proc_mmap; if (mmap) return mmap(file, vma); return -EIO; @@ -497,7 +497,7 @@ static int proc_reg_open(struct inode *inode, struct file *file) if (!use_pde(pde)) return -ENOENT;

- __auto_type release = pde->proc_ops->proc_release; + const auto release = pde->proc_ops->proc_release; if (release) { pdeo = kmem_cache_alloc(pde_opener_cache, GFP_KERNEL); if (!pdeo) { @@ -534,10 +534,9 @@ static int proc_reg_release(struct inode *inode, struct file *file) struct pde_opener *pdeo;

if (pde_is_permanent(pde)) { - __auto_type release = pde->proc_ops->proc_release; - if (release) { + const auto release = pde->proc_ops->proc_release; + if (release) return release(inode, file); - } return 0; }

diff --git a/include/linux/cleanup.h b/include/linux/cleanup.h index 0b55a8f6c59e..8d41b917c77d 100644 --- a/include/linux/cleanup.h +++ b/include/linux/cleanup.h @@ -212,10 +212,10 @@

#define __free(_name) __cleanup(__free_##_name)

-#define __get_and_null(p, nullvalue) \ +#define __get_and_null(p, nullvalue) \ ({ \ - __auto_type __ptr = &(p); \ - __auto_type __val = *__ptr; \ + auto __ptr = &(p); \ + auto __val = *__ptr; \ *__ptr = nullvalue; \ __val; \ }) diff --git a/include/linux/compiler.h b/include/linux/compiler.h index ff71bebe56f5..04487c9bd751 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -190,7 +190,7 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, #define data_race(expr) \ ({ \ __kcsan_disable_current(); \ - __auto_type __v = (expr); \ + auto __v = (expr); \ __kcsan_enable_current(); \ __v; \ }) diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index 3eac51d68426..41172a28ce76 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h @@ -13,6 +13,19 @@

#ifndef __ASSEMBLY__

+/* + * C23 introduces "auto" as a standard way to define type-inferred + * variables, but "auto" has been a (useless) keyword even since K&R C, + * so it has always been "namespace reserved." + * + * Until at some future time we require C23 support, we need the gcc + * extension __auto_type, but there is no reason to put that elsewhere + * in the source code. + */ +#if __STDC_VERSION__ < 202311L +# define auto __auto_type +#endif + /* * Skipped when running bindgen due to a libclang issue; * see https://github.com/rust-lang/rust-bindgen/issues/2244. diff --git a/include/linux/minmax.h b/include/linux/minmax.h index eaaf5c008e4d..a0158db54a04 100644 --- a/include/linux/minmax.h +++ b/include/linux/minmax.h @@ -89,7 +89,7 @@ __cmp_once_unique(op, type, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))

#define __careful_cmp_once(op, x, y, ux, uy) ({ \ - __auto_type ux = (x); __auto_type uy = (y); \ + auto ux = (x); auto uy = (y); \ BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \ #op"("#x", "#y") signedness error"); \ __cmp(op, ux, uy); }) @@ -129,7 +129,7 @@ __careful_cmp(max, (x) + 0u + 0ul + 0ull, (y) + 0u + 0ul + 0ull)

#define __careful_op3(op, x, y, z, ux, uy, uz) ({ \ - __auto_type ux = (x); __auto_type uy = (y);__auto_type uz = (z);\ + auto ux = (x); auto uy = (y); auto uz = (z); \ BUILD_BUG_ON_MSG(!__types_ok3(ux, uy, uz), \ #op"3("#x", "#y", "#z") signedness error"); \ __cmp(op, ux, __cmp(op, uy, uz)); }) @@ -203,7 +203,7 @@ * This macro checks @val/@lo/@hi to make sure they have compatible * signedness. */ -#define clamp(val, lo, hi) __careful_clamp(__auto_type, val, lo, hi) +#define clamp(val, lo, hi) __careful_clamp(auto, val, lo, hi)

/** * clamp_t - return a value clamped to a given range using a given type diff --git a/tools/testing/selftests/bpf/prog_tests/socket_helpers.h b/tools/testing/selftests/bpf/prog_tests/socket_helpers.h index e02cabcc814e..0d59503a0c73 100644 --- a/tools/testing/selftests/bpf/prog_tests/socket_helpers.h +++ b/tools/testing/selftests/bpf/prog_tests/socket_helpers.h @@ -17,11 +17,16 @@ #define VMADDR_CID_LOCAL 1 #endif

+/* include/linux/compiler_types.h */ +#if __STDC_VERSION__ < 202311L && !defined(auto) +# define auto __auto_type +#endif + /* include/linux/cleanup.h */ #define __get_and_null(p, nullvalue) \ ({ \ - __auto_type __ptr = &(p); \ - __auto_type __val = *__ptr; \ + auto __ptr = &(p); \ + auto __val = *__ptr; \ *__ptr = nullvalue; \ __val; \ }) diff --git a/tools/virtio/linux/compiler.h b/tools/virtio/linux/compiler.h index 204ef0e9f542..725b93bfeee1 100644 --- a/tools/virtio/linux/compiler.h +++ b/tools/virtio/linux/compiler.h @@ -31,7 +31,7 @@ */ #define data_race(expr) \ ({ \ - __auto_type __v = (expr); \ + auto __v = (expr); \ __v; \ })