Merge tag 'linux-kselftest-nolibc-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull nolibc updates from Shuah Khan:
 "Nolibc:
   - improved portability by removing build errors with -ENOSYS
   - added syscall6() on MIPS to support pselect6() and mmap()
   - added setvbuf(), rmdir(), pipe(), pipe2()
   - add support for ppc/ppc64
   - environ is no longer optional
   - fixed frame pointer issues at -O0
   - dropped sys_stat() in favor of sys_statx()
   - centralized _start_c() to remove lots of asm code
   - switched size_t to __SIZE_TYPE__

  Selftests:
   - improved status reporting (success/warning/failure counts, path to
     log file)
   - various code cleanups (indent, unused variables, ...)
   - more consistent test numbering
   - enabled compiler warnings
   - dropped unreliable chmod_net test
   - improved reliability (create /dev/zero & /tmp, rely less on /proc)
   - new tests (brk/sbrk/mmap/munmap)
   - improved compatibility with musl
   - new run-nolibc-test target to build and run natively
   - new run-libc-test target to build and run against native libc
   - made the cmdline parser more reliable against boolean arguments
   - dropped dependency on memfd for vfprintf() test
   - nolibc-test is no longer stripped
   - added support for extending ARCH via XARCH

  Other:
   - add Thomas as co-maintainer"

* tag 'linux-kselftest-nolibc-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (103 commits)
  tools/nolibc: avoid undesired casts in the __sysret() macro
  tools/nolibc: keep brk(), sbrk(), mmap() away from __sysret()
  tools/nolibc: silence ppc64 compile warnings
  selftests/nolibc: libc-test: use HOSTCC instead of CC
  tools/nolibc: stackprotector.h: make __stack_chk_init static
  selftests/nolibc: allow report with existing test log
  selftests/nolibc: add test support for ppc64
  selftests/nolibc: add test support for ppc64le
  selftests/nolibc: add test support for ppc
  selftests/nolibc: add XARCH and ARCH mapping support
  tools/nolibc: add support for powerpc64
  tools/nolibc: add support for powerpc
  MAINTAINERS: nolibc: add myself as co-maintainer
  selftests/nolibc: enable compiler warnings
  selftests/nolibc: don't strip nolibc-test
  selftests/nolibc: prevent out of bounds access in expect_vfprintf
  selftests/nolibc: use correct return type for read() and write()
  selftests/nolibc: avoid sign-compare warnings
  selftests/nolibc: avoid unused parameter warnings
  selftests/nolibc: make functions static if possible
  ...

23 files changed, 1221 insertions, 1166 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 7f6426284e73..4b8d634f3a4e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15010,6 +15010,7 @@ F:	include/linux/power/bq27xxx_battery.h
 
 NOLIBC HEADER FILE
 M:	Willy Tarreau <w@1wt.eu>
+M:	Thomas Weißschuh <linux@weissschuh.net>
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/wtarreau/nolibc.git
 F:	tools/include/nolibc/
diff --git a/tools/include/nolibc/Makefile b/tools/include/nolibc/Makefile
index 64d67b080744..909b6eb500fe 100644
--- a/tools/include/nolibc/Makefile
+++ b/tools/include/nolibc/Makefile
@@ -27,6 +27,7 @@ nolibc_arch := $(patsubst arm64,aarch64,$(ARCH))
 arch_file := arch-$(nolibc_arch).h
 all_files := \
 		compiler.h \
+		crt.h \
 		ctype.h \
 		errno.h \
 		nolibc.h \
diff --git a/tools/include/nolibc/arch-aarch64.h b/tools/include/nolibc/arch-aarch64.h
index 11f294a406b7..6c33c46848e3 100644
--- a/tools/include/nolibc/arch-aarch64.h
+++ b/tools/include/nolibc/arch-aarch64.h
@@ -8,34 +8,7 @@
 #define _NOLIBC_ARCH_AARCH64_H
 
 #include "compiler.h"
-
-/* The struct returned by the newfstatat() syscall. Differs slightly from the
- * x86_64's stat one by field ordering, so be careful.
- */
-struct sys_stat_struct {
-	unsigned long   st_dev;
-	unsigned long   st_ino;
-	unsigned int    st_mode;
-	unsigned int    st_nlink;
-	unsigned int    st_uid;
-	unsigned int    st_gid;
-
-	unsigned long   st_rdev;
-	unsigned long   __pad1;
-	long            st_size;
-	int             st_blksize;
-	int             __pad2;
-
-	long            st_blocks;
-	long            st_atime;
-	unsigned long   st_atime_nsec;
-	long            st_mtime;
-
-	unsigned long   st_mtime_nsec;
-	long            st_ctime;
-	unsigned long   st_ctime_nsec;
-	unsigned int    __unused[2];
-};
+#include "crt.h"
 
 /* Syscalls for AARCH64 :
  *   - registers are 64-bit
@@ -56,8 +29,8 @@ struct sys_stat_struct {
 ({                                                                            \
 	register long _num  __asm__ ("x8") = (num);                           \
 	register long _arg1 __asm__ ("x0");                                   \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"svc #0\n"                                                    \
 		: "=r"(_arg1)                                                 \
 		: "r"(_num)                                                   \
@@ -70,8 +43,8 @@ struct sys_stat_struct {
 ({                                                                            \
 	register long _num  __asm__ ("x8") = (num);                           \
 	register long _arg1 __asm__ ("x0") = (long)(arg1);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"svc #0\n"                                                    \
 		: "=r"(_arg1)                                                 \
 		: "r"(_arg1),                                                 \
@@ -86,8 +59,8 @@ struct sys_stat_struct {
 	register long _num  __asm__ ("x8") = (num);                           \
 	register long _arg1 __asm__ ("x0") = (long)(arg1);                    \
 	register long _arg2 __asm__ ("x1") = (long)(arg2);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"svc #0\n"                                                    \
 		: "=r"(_arg1)                                                 \
 		: "r"(_arg1), "r"(_arg2),                                     \
@@ -103,8 +76,8 @@ struct sys_stat_struct {
 	register long _arg1 __asm__ ("x0") = (long)(arg1);                    \
 	register long _arg2 __asm__ ("x1") = (long)(arg2);                    \
 	register long _arg3 __asm__ ("x2") = (long)(arg3);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"svc #0\n"                                                    \
 		: "=r"(_arg1)                                                 \
 		: "r"(_arg1), "r"(_arg2), "r"(_arg3),                         \
@@ -121,8 +94,8 @@ struct sys_stat_struct {
 	register long _arg2 __asm__ ("x1") = (long)(arg2);                    \
 	register long _arg3 __asm__ ("x2") = (long)(arg3);                    \
 	register long _arg4 __asm__ ("x3") = (long)(arg4);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"svc #0\n"                                                    \
 		: "=r"(_arg1)                                                 \
 		: "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4),             \
@@ -140,8 +113,8 @@ struct sys_stat_struct {
 	register long _arg3 __asm__ ("x2") = (long)(arg3);                    \
 	register long _arg4 __asm__ ("x3") = (long)(arg4);                    \
 	register long _arg5 __asm__ ("x4") = (long)(arg5);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"svc #0\n"                                                    \
 		: "=r" (_arg1)                                                \
 		: "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \
@@ -160,8 +133,8 @@ struct sys_stat_struct {
 	register long _arg4 __asm__ ("x3") = (long)(arg4);                    \
 	register long _arg5 __asm__ ("x4") = (long)(arg5);                    \
 	register long _arg6 __asm__ ("x5") = (long)(arg6);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"svc #0\n"                                                    \
 		: "=r" (_arg1)                                                \
 		: "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \
@@ -171,33 +144,13 @@ struct sys_stat_struct {
 	_arg1;                                                                \
 })
 
-char **environ __attribute__((weak));
-const unsigned long *_auxv __attribute__((weak));
-
 /* startup code */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
-#ifdef _NOLIBC_STACKPROTECTOR
-		"bl __stack_chk_init\n"   /* initialize stack protector                     */
-#endif
-		"ldr x0, [sp]\n"     /* argc (x0) was in the stack                          */
-		"add x1, sp, 8\n"    /* argv (x1) = sp                                      */
-		"lsl x2, x0, 3\n"    /* envp (x2) = 8*argc ...                              */
-		"add x2, x2, 8\n"    /*           + 8 (skip null)                           */
-		"add x2, x2, x1\n"   /*           + argv                                    */
-		"adrp x3, environ\n"          /* x3 = &environ (high bits)                  */
-		"str x2, [x3, #:lo12:environ]\n" /* store envp into environ                 */
-		"mov x4, x2\n"       /* search for auxv (follows NULL after last env)       */
-		"0:\n"
-		"ldr x5, [x4], 8\n"  /* x5 = *x4; x4 += 8                                   */
-		"cbnz x5, 0b\n"      /* and stop at NULL after last env                     */
-		"adrp x3, _auxv\n"   /* x3 = &_auxv (high bits)                             */
-		"str x4, [x3, #:lo12:_auxv]\n" /* store x4 into _auxv                       */
-		"and sp, x1, -16\n"  /* sp must be 16-byte aligned in the callee            */
-		"bl main\n"          /* main() returns the status code, we'll exit with it. */
-		"mov x8, 93\n"       /* NR_exit == 93                                       */
-		"svc #0\n"
+		"mov x0, sp\n"          /* save stack pointer to x0, as arg1 of _start_c */
+		"and sp, x0, -16\n"     /* sp must be 16-byte aligned in the callee      */
+		"bl  _start_c\n"        /* transfer to c runtime                         */
 	);
 	__builtin_unreachable();
 }
diff --git a/tools/include/nolibc/arch-arm.h b/tools/include/nolibc/arch-arm.h
index ca4c66987497..cae4afa7c1c7 100644
--- a/tools/include/nolibc/arch-arm.h
+++ b/tools/include/nolibc/arch-arm.h
@@ -8,43 +8,7 @@
 #define _NOLIBC_ARCH_ARM_H
 
 #include "compiler.h"
-
-/* The struct returned by the stat() syscall, 32-bit only, the syscall returns
- * exactly 56 bytes (stops before the unused array). In big endian, the format
- * differs as devices are returned as short only.
- */
-struct sys_stat_struct {
-#if defined(__ARMEB__)
-	unsigned short st_dev;
-	unsigned short __pad1;
-#else
-	unsigned long  st_dev;
-#endif
-	unsigned long  st_ino;
-	unsigned short st_mode;
-	unsigned short st_nlink;
-	unsigned short st_uid;
-	unsigned short st_gid;
-
-#if defined(__ARMEB__)
-	unsigned short st_rdev;
-	unsigned short __pad2;
-#else
-	unsigned long  st_rdev;
-#endif
-	unsigned long  st_size;
-	unsigned long  st_blksize;
-	unsigned long  st_blocks;
-
-	unsigned long  st_atime;
-	unsigned long  st_atime_nsec;
-	unsigned long  st_mtime;
-	unsigned long  st_mtime_nsec;
-
-	unsigned long  st_ctime;
-	unsigned long  st_ctime_nsec;
-	unsigned long  __unused[2];
-};
+#include "crt.h"
 
 /* Syscalls for ARM in ARM or Thumb modes :
  *   - registers are 32-bit
@@ -90,8 +54,8 @@ struct sys_stat_struct {
 ({                                                                            \
 	register long _num  __asm__(_NOLIBC_SYSCALL_REG) = (num);             \
 	register long _arg1 __asm__ ("r0");                                   \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		_NOLIBC_THUMB_SET_R7                                          \
 		"svc #0\n"                                                    \
 		_NOLIBC_THUMB_RESTORE_R7                                      \
@@ -107,8 +71,8 @@ struct sys_stat_struct {
 ({                                                                            \
 	register long _num  __asm__(_NOLIBC_SYSCALL_REG) = (num);             \
 	register long _arg1 __asm__ ("r0") = (long)(arg1);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		_NOLIBC_THUMB_SET_R7                                          \
 		"svc #0\n"                                                    \
 		_NOLIBC_THUMB_RESTORE_R7                                      \
@@ -125,8 +89,8 @@ struct sys_stat_struct {
 	register long _num  __asm__(_NOLIBC_SYSCALL_REG) = (num);             \
 	register long _arg1 __asm__ ("r0") = (long)(arg1);                    \
 	register long _arg2 __asm__ ("r1") = (long)(arg2);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		_NOLIBC_THUMB_SET_R7                                          \
 		"svc #0\n"                                                    \
 		_NOLIBC_THUMB_RESTORE_R7                                      \
@@ -144,8 +108,8 @@ struct sys_stat_struct {
 	register long _arg1 __asm__ ("r0") = (long)(arg1);                    \
 	register long _arg2 __asm__ ("r1") = (long)(arg2);                    \
 	register long _arg3 __asm__ ("r2") = (long)(arg3);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		_NOLIBC_THUMB_SET_R7                                          \
 		"svc #0\n"                                                    \
 		_NOLIBC_THUMB_RESTORE_R7                                      \
@@ -164,8 +128,8 @@ struct sys_stat_struct {
 	register long _arg2 __asm__ ("r1") = (long)(arg2);                    \
 	register long _arg3 __asm__ ("r2") = (long)(arg3);                    \
 	register long _arg4 __asm__ ("r3") = (long)(arg4);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		_NOLIBC_THUMB_SET_R7                                          \
 		"svc #0\n"                                                    \
 		_NOLIBC_THUMB_RESTORE_R7                                      \
@@ -185,8 +149,8 @@ struct sys_stat_struct {
 	register long _arg3 __asm__ ("r2") = (long)(arg3);                    \
 	register long _arg4 __asm__ ("r3") = (long)(arg4);                    \
 	register long _arg5 __asm__ ("r4") = (long)(arg5);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		_NOLIBC_THUMB_SET_R7                                          \
 		"svc #0\n"                                                    \
 		_NOLIBC_THUMB_RESTORE_R7                                      \
@@ -207,8 +171,8 @@ struct sys_stat_struct {
 	register long _arg4 __asm__ ("r3") = (long)(arg4);                    \
 	register long _arg5 __asm__ ("r4") = (long)(arg5);                    \
 	register long _arg6 __asm__ ("r5") = (long)(arg6);                    \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		_NOLIBC_THUMB_SET_R7                                          \
 		"svc #0\n"                                                    \
 		_NOLIBC_THUMB_RESTORE_R7                                      \
@@ -220,49 +184,14 @@ struct sys_stat_struct {
 	_arg1;                                                                \
 })
 
-
-char **environ __attribute__((weak));
-const unsigned long *_auxv __attribute__((weak));
-
 /* startup code */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
-#ifdef _NOLIBC_STACKPROTECTOR
-		"bl __stack_chk_init\n"       /* initialize stack protector                          */
-#endif
-		"pop {%r0}\n"                 /* argc was in the stack                               */
-		"mov %r1, %sp\n"              /* argv = sp                                           */
-
-		"add %r2, %r0, $1\n"          /* envp = (argc + 1) ...                               */
-		"lsl %r2, %r2, $2\n"          /*        * 4        ...                               */
-		"add %r2, %r2, %r1\n"         /*        + argv                                       */
-		"ldr %r3, 1f\n"               /* r3 = &environ (see below)                           */
-		"str %r2, [r3]\n"             /* store envp into environ                             */
-
-		"mov r4, r2\n"                /* search for auxv (follows NULL after last env)       */
-		"0:\n"
-		"mov r5, r4\n"                /* r5 = r4                                             */
-		"add r4, r4, #4\n"            /* r4 += 4                                             */
-		"ldr r5,[r5]\n"               /* r5 = *r5 = *(r4-4)                                  */
-		"cmp r5, #0\n"                /* and stop at NULL after last env                     */
-		"bne 0b\n"
-		"ldr %r3, 2f\n"               /* r3 = &_auxv (low bits)                              */
-		"str r4, [r3]\n"              /* store r4 into _auxv                                 */
-
-		"mov %r3, $8\n"               /* AAPCS : sp must be 8-byte aligned in the            */
-		"neg %r3, %r3\n"              /*         callee, and bl doesn't push (lr=pc)         */
-		"and %r3, %r3, %r1\n"         /* so we do sp = r1(=sp) & r3(=-8);                    */
-		"mov %sp, %r3\n"
-
-		"bl main\n"                   /* main() returns the status code, we'll exit with it. */
-		"movs r7, $1\n"               /* NR_exit == 1                                        */
-		"svc $0x00\n"
-		".align 2\n"                  /* below are the pointers to a few variables           */
-		"1:\n"
-		".word environ\n"
-		"2:\n"
-		".word _auxv\n"
+		"mov %r0, sp\n"         /* save stack pointer to %r0, as arg1 of _start_c */
+		"and ip, %r0, #-8\n"    /* sp must be 8-byte aligned in the callee        */
+		"mov sp, ip\n"
+		"bl  _start_c\n"        /* transfer to c runtime                          */
 	);
 	__builtin_unreachable();
 }
diff --git a/tools/include/nolibc/arch-i386.h b/tools/include/nolibc/arch-i386.h
index 3d672d925e9e..64415b9fac77 100644
--- a/tools/include/nolibc/arch-i386.h
+++ b/tools/include/nolibc/arch-i386.h
@@ -8,32 +8,7 @@
 #define _NOLIBC_ARCH_I386_H
 
 #include "compiler.h"
-
-/* The struct returned by the stat() syscall, 32-bit only, the syscall returns
- * exactly 56 bytes (stops before the unused array).
- */
-struct sys_stat_struct {
-	unsigned long  st_dev;
-	unsigned long  st_ino;
-	unsigned short st_mode;
-	unsigned short st_nlink;
-	unsigned short st_uid;
-	unsigned short st_gid;
-
-	unsigned long  st_rdev;
-	unsigned long  st_size;
-	unsigned long  st_blksize;
-	unsigned long  st_blocks;
-
-	unsigned long  st_atime;
-	unsigned long  st_atime_nsec;
-	unsigned long  st_mtime;
-	unsigned long  st_mtime_nsec;
-
-	unsigned long  st_ctime;
-	unsigned long  st_ctime_nsec;
-	unsigned long  __unused[2];
-};
+#include "crt.h"
 
 /* Syscalls for i386 :
  *   - mostly similar to x86_64
@@ -57,8 +32,8 @@ struct sys_stat_struct {
 ({                                                                            \
 	long _ret;                                                            \
 	register long _num __asm__ ("eax") = (num);                           \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"int $0x80\n"                                                 \
 		: "=a" (_ret)                                                 \
 		: "0"(_num)                                                   \
@@ -72,8 +47,8 @@ struct sys_stat_struct {
 	long _ret;                                                            \
 	register long _num __asm__ ("eax") = (num);                           \
 	register long _arg1 __asm__ ("ebx") = (long)(arg1);                   \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"int $0x80\n"                                                 \
 		: "=a" (_ret)                                                 \
 		: "r"(_arg1),                                                 \
@@ -89,8 +64,8 @@ struct sys_stat_struct {
 	register long _num __asm__ ("eax") = (num);                           \
 	register long _arg1 __asm__ ("ebx") = (long)(arg1);                   \
 	register long _arg2 __asm__ ("ecx") = (long)(arg2);                   \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"int $0x80\n"                                                 \
 		: "=a" (_ret)                                                 \
 		: "r"(_arg1), "r"(_arg2),                                     \
@@ -107,8 +82,8 @@ struct sys_stat_struct {
 	register long _arg1 __asm__ ("ebx") = (long)(arg1);                   \
 	register long _arg2 __asm__ ("ecx") = (long)(arg2);                   \
 	register long _arg3 __asm__ ("edx") = (long)(arg3);                   \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"int $0x80\n"                                                 \
 		: "=a" (_ret)                                                 \
 		: "r"(_arg1), "r"(_arg2), "r"(_arg3),                         \
@@ -126,8 +101,8 @@ struct sys_stat_struct {
 	register long _arg2 __asm__ ("ecx") = (long)(arg2);                   \
 	register long _arg3 __asm__ ("edx") = (long)(arg3);                   \
 	register long _arg4 __asm__ ("esi") = (long)(arg4);                   \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"int $0x80\n"                                                 \
 		: "=a" (_ret)                                                 \
 		: "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4),             \
@@ -146,8 +121,8 @@ struct sys_stat_struct {
 	register long _arg3 __asm__ ("edx") = (long)(arg3);                   \
 	register long _arg4 __asm__ ("esi") = (long)(arg4);                   \
 	register long _arg5 __asm__ ("edi") = (long)(arg5);                   \
-	                                                                      \
-	__asm__  volatile (                                                   \
+									      \
+	__asm__ volatile (                                                    \
 		"int $0x80\n"                                                 \
 		: "=a" (_ret)                                                 \
 		: "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \
@@ -180,9 +155,6 @@ struct sys_stat_struct {
 	_eax;							\
 })
 
-char **environ __attribute__((weak));
-const unsigned long *_auxv __attribute__((weak));
-
 /* startup code */
 /*
  * i386 System V ABI mandates:
@@ -190,33 +162,15 @@ const unsigned long *_auxv __attribute__((weak));
  * 2) The deepest stack frame should be set to zero
  *
  */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
-#ifdef _NOLIBC_STACKPROTECTOR
-		"call __stack_chk_init\n"   /* initialize stack protector                    */
-#endif
-		"pop %eax\n"                /* argc   (first arg, %eax)                      */
-		"mov %esp, %ebx\n"          /* argv[] (second arg, %ebx)                     */
-		"lea 4(%ebx,%eax,4),%ecx\n" /* then a NULL then envp (third arg, %ecx)       */
-		"mov %ecx, environ\n"       /* save environ                                  */
-		"xor %ebp, %ebp\n"          /* zero the stack frame                          */
-		"mov %ecx, %edx\n"          /* search for auxv (follows NULL after last env) */
-		"0:\n"
-		"add $4, %edx\n"            /* search for auxv using edx, it follows the     */
-		"cmp -4(%edx), %ebp\n"      /* ... NULL after last env (ebp is zero here)    */
-		"jnz 0b\n"
-		"mov %edx, _auxv\n"         /* save it into _auxv                            */
-		"and $-16, %esp\n"          /* x86 ABI : esp must be 16-byte aligned before  */
-		"sub $4, %esp\n"            /* the call instruction (args are aligned)       */
-		"push %ecx\n"               /* push all registers on the stack so that we    */
-		"push %ebx\n"               /* support both regparm and plain stack modes    */
-		"push %eax\n"
-		"call main\n"               /* main() returns the status code in %eax        */
-		"mov %eax, %ebx\n"          /* retrieve exit code (32-bit int)               */
-		"movl $1, %eax\n"           /* NR_exit == 1                                  */
-		"int $0x80\n"               /* exit now                                      */
-		"hlt\n"                     /* ensure it does not                            */
+		"xor  %ebp, %ebp\n"       /* zero the stack frame                                */
+		"mov  %esp, %eax\n"       /* save stack pointer to %eax, as arg1 of _start_c     */
+		"and  $-16, %esp\n"       /* last pushed argument must be 16-byte aligned        */
+		"push %eax\n"             /* push arg1 on stack to support plain stack modes too */
+		"call _start_c\n"         /* transfer to c runtime                               */
+		"hlt\n"                   /* ensure it does not return                           */
 	);
 	__builtin_unreachable();
 }
diff --git a/tools/include/nolibc/arch-loongarch.h b/tools/include/nolibc/arch-loongarch.h
index ad3f266e7093..bf98f6220195 100644
--- a/tools/include/nolibc/arch-loongarch.h
+++ b/tools/include/nolibc/arch-loongarch.h
@@ -8,6 +8,7 @@
 #define _NOLIBC_ARCH_LOONGARCH_H
 
 #include "compiler.h"
+#include "crt.h"
 
 /* Syscalls for LoongArch :
  *   - stack is 16-byte aligned
@@ -22,18 +23,19 @@
  * On LoongArch, select() is not implemented so we have to use pselect6().
  */
 #define __ARCH_WANT_SYS_PSELECT6
+#define _NOLIBC_SYSCALL_CLOBBERLIST \
+	"memory", "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7", "$t8"
 
 #define my_syscall0(num)                                                      \
 ({                                                                            \
 	register long _num  __asm__ ("a7") = (num);                           \
 	register long _arg1 __asm__ ("a0");                                   \
 									      \
-	__asm__  volatile (                                                   \
+	__asm__ volatile (                                                    \
 		"syscall 0\n"                                                 \
 		: "=r"(_arg1)                                                 \
 		: "r"(_num)                                                   \
-		: "memory", "$t0", "$t1", "$t2", "$t3",                       \
-		  "$t4", "$t5", "$t6", "$t7", "$t8"                           \
+		: _NOLIBC_SYSCALL_CLOBBERLIST                                 \
 	);                                                                    \
 	_arg1;                                                                \
 })
@@ -43,12 +45,11 @@
 	register long _num  __asm__ ("a7") = (num);                           \
 	register long _arg1 __asm__ ("a0") = (long)(arg1);		      \
 									      \
-	__asm__  volatile (                                                   \
+	__asm__ volatile (                                                    \
 		"syscall 0\n"                                                 \
 		: "+r"(_arg1)                                                 \
 		: "r"(_num)                                                   \
-		: "memory", "$t0", "$t1", "$t2", "$t3",                       \
-		  "$t4", "$t5", "$t6", "$t7", "$t8"                           \
+		: _NOLIBC_SYSCALL_CLOBBERLIST                                 \
 	);                                                                    \
 	_arg1;                                                                \
 })
@@ -59,13 +60,12 @@
 	register long _arg1 __asm__ ("a0") = (long)(arg1);                    \
 	register long _arg2 __asm__ ("a1") = (long)(arg2);                    \
 									      \
-	__asm__  volatile (                                                   \
+	__asm__ volatile (                                                    \
 		"syscall 0\n"                                                 \
 		: "+r"(_arg1)                                                 \
 		: "r"(_arg2),                                                 \
 		  "r"(_num)                                                   \
-		: "memory", "$t0", "$t1", "$t2", "$t3",                       \
-		  "$t4", "$t5", "$t6", "$t7", "$t8"                           \
+		: _NOLIBC_SYSCALL_CLOBBERLIST                                 \
 	);                                                                    \
 	_arg1;                                                                \
 })
@@ -77,13 +77,12 @@
 	register long _arg2 __asm__ ("a1") = (long)(arg2);                    \
 	register long _arg3 __asm__ ("a2") = (long)(arg3);                    \
 									      \
-	__asm__  volatile (                                                   \
+	__asm__ volatile (                                                    \
 		"syscall 0\n"                                                 \
 		: "+r"(_arg1)                                                 \
 		: "r"(_arg2), "r"(_arg3),                                     \
 		  "r"(_num)                                                   \
-		: "memory", "$t0", "$t1", "$t2", "$t3",                       \
-		  "$t4", "$t5", "$t6", "$t7", "$t8"                           \
+		: _NOLIBC_SYSCALL_CLOBBERLIST                                 \
 	);                                                                    \
 	_arg1;