diff --git a/tools/include/nolibc/arch-aarch64.h b/tools/include/nolibc/arch-aarch64.h
index f68baf8f395fd..4d263661411f3 100644
--- a/tools/include/nolibc/arch-aarch64.h
+++ b/tools/include/nolibc/arch-aarch64.h
@@ -182,18 +182,19 @@ struct sys_stat_struct {
 })
 
 /* startup code */
-__asm__ (".section .text\n"
-    ".weak _start\n"
-    "_start:\n"
-    "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
-    "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"
-    "");
-
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+{
+	__asm__ volatile (
+		"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
+		"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"
+	);
+	__builtin_unreachable();
+}
 #endif // _NOLIBC_ARCH_AARCH64_H
diff --git a/tools/include/nolibc/arch-arm.h b/tools/include/nolibc/arch-arm.h
index f31be8e967d68..875b219751373 100644
--- a/tools/include/nolibc/arch-arm.h
+++ b/tools/include/nolibc/arch-arm.h
@@ -175,30 +175,20 @@ struct sys_stat_struct {
 })
 
 /* startup code */
-__asm__ (".section .text\n"
-    ".weak _start\n"
-    "_start:\n"
-#if defined(__THUMBEB__) || defined(__THUMBEL__)
-    /* We enter here in 32-bit mode but if some previous functions were in
-     * 16-bit mode, the assembler cannot know, so we need to tell it we're in
-     * 32-bit now, then switch to 16-bit (is there a better way to do it than
-     * adding 1 by hand ?) and tell the asm we're now in 16-bit mode so that
-     * it generates correct instructions. Note that we do not support thumb1.
-     */
-    ".code 32\n"
-    "add     r0, pc, #1\n"
-    "bx      r0\n"
-    ".code 16\n"
-#endif
-    "pop {%r0}\n"                 // argc was in the stack
-    "mov %r1, %sp\n"              // argv = sp
-    "add %r2, %r1, %r0, lsl #2\n" // envp = argv + 4*argc ...
-    "add %r2, %r2, $4\n"          //        ... + 4
-    "and %r3, %r1, $-8\n"         // AAPCS : sp must be 8-byte aligned in the
-    "mov %sp, %r3\n"              //         callee, an bl doesn't push (lr=pc)
-    "bl main\n"                   // main() returns the status code, we'll exit with it.
-    "movs r7, $1\n"               // NR_exit == 1
-    "svc $0x00\n"
-    "");
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+{
+	__asm__ volatile (
+		"pop {%r0}\n"                 // argc was in the stack
+		"mov %r1, %sp\n"              // argv = sp
+		"add %r2, %r1, %r0, lsl #2\n" // envp = argv + 4*argc ...
+		"add %r2, %r2, $4\n"          //        ... + 4
+		"and %r3, %r1, $-8\n"         // AAPCS : sp must be 8-byte aligned in the
+		"mov %sp, %r3\n"              //         callee, an bl doesn't push (lr=pc)
+		"bl main\n"                   // main() returns the status code, we'll exit with it.
+		"movs r7, $1\n"               // NR_exit == 1
+		"svc $0x00\n"
+	  );
+	__builtin_unreachable();
+}
 
 #endif // _NOLIBC_ARCH_ARM_H
diff --git a/tools/include/nolibc/arch-i386.h b/tools/include/nolibc/arch-i386.h
index d7e7212346e2f..b1bed2d87f741 100644
--- a/tools/include/nolibc/arch-i386.h
+++ b/tools/include/nolibc/arch-i386.h
@@ -197,23 +197,25 @@ struct sys_stat_struct {
  * 2) The deepest stack frame should be set to zero
  *
  */
-__asm__ (".section .text\n"
-    ".weak _start\n"
-    "_start:\n"
-    "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)
-    "xor %ebp, %ebp\n"          // zero the stack frame
-    "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
-    "");
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+{
+	__asm__ volatile (
+		"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)
+		"xor %ebp, %ebp\n"          // zero the stack frame
+		"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
+	);
+	__builtin_unreachable();
+}
 
 #endif // _NOLIBC_ARCH_I386_H
diff --git a/tools/include/nolibc/arch-mips.h b/tools/include/nolibc/arch-mips.h
index 7380093ba9e7d..11270ef25ea57 100644
--- a/tools/include/nolibc/arch-mips.h
+++ b/tools/include/nolibc/arch-mips.h
@@ -189,29 +189,32 @@ struct sys_stat_struct {
 })
 
 /* startup code, note that it's called __start on MIPS */
-__asm__ (".section .text\n"
-    ".weak __start\n"
-    ".set nomips16\n"
-    ".set push\n"
-    ".set    noreorder\n"
-    ".option pic0\n"
-    ".ent __start\n"
-    "__start:\n"
-    "lw $a0,($sp)\n"              // argc was in the stack
-    "addiu  $a1, $sp, 4\n"        // argv = sp + 4
-    "sll $a2, $a0, 2\n"           // a2 = argc * 4
-    "add   $a2, $a2, $a1\n"       // envp = argv + 4*argc ...
-    "addiu $a2, $a2, 4\n"         //        ... + 4
-    "li $t0, -8\n"
-    "and $sp, $sp, $t0\n"         // sp must be 8-byte aligned
-    "addiu $sp,$sp,-16\n"         // the callee expects to save a0..a3 there!
-    "jal main\n"                  // main() returns the status code, we'll exit with it.
-    "nop\n"                       // delayed slot
-    "move $a0, $v0\n"             // retrieve 32-bit exit code from v0
-    "li $v0, 4001\n"              // NR_exit == 4001
-    "syscall\n"
-    ".end __start\n"
-    ".set pop\n"
-    "");
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __start(void)
+{
+	__asm__ volatile (
+		//".set nomips16\n"
+		".set push\n"
+		".set    noreorder\n"
+		".option pic0\n"
+		//".ent __start\n"
+		//"__start:\n"
+		"lw $a0,($sp)\n"        // argc was in the stack
+		"addiu  $a1, $sp, 4\n"  // argv = sp + 4
+		"sll $a2, $a0, 2\n"     // a2 = argc * 4
+		"add   $a2, $a2, $a1\n" // envp = argv + 4*argc ...
+		"addiu $a2, $a2, 4\n"   //        ... + 4
+		"li $t0, -8\n"
+		"and $sp, $sp, $t0\n"   // sp must be 8-byte aligned
+		"addiu $sp,$sp,-16\n"   // the callee expects to save a0..a3 there!
+		"jal main\n"            // main() returns the status code, we'll exit with it.
+		"nop\n"                 // delayed slot
+		"move $a0, $v0\n"       // retrieve 32-bit exit code from v0
+		"li $v0, 4001\n"        // NR_exit == 4001
+		"syscall\n"
+		//".end __start\n"
+		".set pop\n"
+	);
+	__builtin_unreachable();
+}
 
 #endif // _NOLIBC_ARCH_MIPS_H
diff --git a/tools/include/nolibc/arch-riscv.h b/tools/include/nolibc/arch-riscv.h
index a3bdd9803f8cb..bee769e6885c6 100644
--- a/tools/include/nolibc/arch-riscv.h
+++ b/tools/include/nolibc/arch-riscv.h
@@ -183,22 +183,24 @@ struct sys_stat_struct {
 })
 
 /* startup code */
-__asm__ (".section .text\n"
-    ".weak _start\n"
-    "_start:\n"
-    ".option push\n"
-    ".option norelax\n"
-    "lla   gp, __global_pointer$\n"
-    ".option pop\n"
-    "lw    a0, 0(sp)\n"          // argc (a0) was in the stack
-    "add   a1, sp, "SZREG"\n"    // argv (a1) = sp
-    "slli  a2, a0, "PTRLOG"\n"   // envp (a2) = SZREG*argc ...
-    "add   a2, a2, "SZREG"\n"    //             + SZREG (skip null)
-    "add   a2,a2,a1\n"           //             + argv
-    "andi  sp,a1,-16\n"          // sp must be 16-byte aligned
-    "call  main\n"               // main() returns the status code, we'll exit with it.
-    "li a7, 93\n"                // NR_exit == 93
-    "ecall\n"
-    "");
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+{
+	__asm__ volatile (
+		".option push\n"
+		".option norelax\n"
+		"lla   gp, __global_pointer$\n"
+		".option pop\n"
+		"lw    a0, 0(sp)\n"          // argc (a0) was in the stack
+		"add   a1, sp, "SZREG"\n"    // argv (a1) = sp
+		"slli  a2, a0, "PTRLOG"\n"   // envp (a2) = SZREG*argc ...
+		"add   a2, a2, "SZREG"\n"    //             + SZREG (skip null)
+		"add   a2,a2,a1\n"           //             + argv
+		"andi  sp,a1,-16\n"          // sp must be 16-byte aligned
+		"call  main\n"               // main() returns the status code, we'll exit with it.
+		"li a7, 93\n"                // NR_exit == 93
+		"ecall\n"
+	);
+	__builtin_unreachable();
+}
 
 #endif // _NOLIBC_ARCH_RISCV_H
diff --git a/tools/include/nolibc/arch-s390.h b/tools/include/nolibc/arch-s390.h
index 76bc8fdaf9226..2c0b8847c0507 100644
--- a/tools/include/nolibc/arch-s390.h
+++ b/tools/include/nolibc/arch-s390.h
@@ -172,27 +172,29 @@ struct sys_stat_struct {
 })
 
 /* startup code */
-__asm__ (".section .text\n"
-	 ".weak _start\n"
-	 "_start:\n"
-	 "lg	%r2,0(%r15)\n"		/* argument count */
-	 "la	%r3,8(%r15)\n"		/* argument pointers */
-
-	 "xgr	%r0,%r0\n"		/* r0 will be our NULL value */
-	 /* search for envp */
-	 "lgr	%r4,%r3\n"		/* start at argv */
-	 "0:\n"
-	 "clg	%r0,0(%r4)\n"		/* entry zero? */
-	 "la	%r4,8(%r4)\n"		/* advance pointer */
-	 "jnz	0b\n"			/* no -> test next pointer */
-					/* yes -> r4 now contains start of envp */
-
-	 "aghi	%r15,-160\n"		/* allocate new stackframe */
-	 "xc	0(8,%r15),0(%r15)\n"	/* clear backchain */
-	 "brasl	%r14,main\n"		/* ret value of main is arg to exit */
-	 "lghi	%r1,1\n"		/* __NR_exit */
-	 "svc	0\n"
-	 "");
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+{
+	__asm__ volatile (
+		"lg	%r2,0(%r15)\n"		/* argument count */
+		"la	%r3,8(%r15)\n"		/* argument pointers */
+
+		"xgr	%r0,%r0\n"		/* r0 will be our NULL value */
+		/* search for envp */
+		"lgr	%r4,%r3\n"		/* start at argv */
+		"0:\n"
+		"clg	%r0,0(%r4)\n"		/* entry zero? */
+		"la	%r4,8(%r4)\n"		/* advance pointer */
+		"jnz	0b\n"			/* no -> test next pointer */
+						/* yes -> r4 now contains start of envp */
+
+		"aghi	%r15,-160\n"		/* allocate new stackframe */
+		"xc	0(8,%r15),0(%r15)\n"	/* clear backchain */
+		"brasl	%r14,main\n"		/* ret value of main is arg to exit */
+		"lghi	%r1,1\n"		/* __NR_exit */
+		"svc	0\n"
+	);
+	__builtin_unreachable();
+}
 
 struct s390_mmap_arg_struct {
 	unsigned long addr;
diff --git a/tools/include/nolibc/arch-x86_64.h b/tools/include/nolibc/arch-x86_64.h
index 0e1e9eb8545d6..c70a84612a9e6 100644
--- a/tools/include/nolibc/arch-x86_64.h
+++ b/tools/include/nolibc/arch-x86_64.h
@@ -197,19 +197,21 @@ struct sys_stat_struct {
  * 2) The deepest stack frame should be zero (the %rbp).
  *
  */
-__asm__ (".section .text\n"
-    ".weak _start\n"
-    "_start:\n"
-    "pop %rdi\n"                // argc   (first arg, %rdi)
-    "mov %rsp, %rsi\n"          // argv[] (second arg, %rsi)
-    "lea 8(%rsi,%rdi,8),%rdx\n" // then a NULL then envp (third arg, %rdx)
-    "xor %ebp, %ebp\n"          // zero the stack frame
-    "and $-16, %rsp\n"          // x86 ABI : esp must be 16-byte aligned before call
-    "call main\n"               // main() returns the status code, we'll exit with it.
-    "mov %eax, %edi\n"          // retrieve exit code (32 bit)
-    "mov $60, %eax\n"           // NR_exit == 60
-    "syscall\n"                 // really exit
-    "hlt\n"                     // ensure it does not return
-    "");
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+{
+	__asm__ volatile (
+		"pop %rdi\n"                // argc   (first arg, %rdi)
+		"mov %rsp, %rsi\n"          // argv[] (second arg, %rsi)
+		"lea 8(%rsi,%rdi,8),%rdx\n" // then a NULL then envp (third arg, %rdx)
+		"xor %ebp, %ebp\n"          // zero the stack frame
+		"and $-16, %rsp\n"          // x86 ABI : esp must be 16-byte aligned before call
+		"call main\n"               // main() returns the status code, we'll exit with it.
+		"mov %eax, %edi\n"          // retrieve exit code (32 bit)
+		"mov $60, %eax\n"           // NR_exit == 60
+		"syscall\n"                 // really exit
+		"hlt\n"                     // ensure it does not return
+	);
+	__builtin_unreachable();
+}
 
 #endif // _NOLIBC_ARCH_X86_64_H