From 6ea2987c9a7b6c5f37d08a3eaa664c9ff7467670 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Thu, 25 Jul 2024 18:54:18 +0200
Subject: tools/nolibc: include arch.h from string.h
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

string.h tests for the macros NOLIBC_ARCH_HAS_$FUNC to use the
architecture-optimized function variants.
However if string.h is included before arch.h header then that check
does not work, leading to duplicate function definitions.

Fixes: 553845eebd60 ("tools/nolibc: x86-64: Use `rep movsb` for `memcpy()` and `memmove()`")
Fixes: 12108aa8c1a1 ("tools/nolibc: x86-64: Use `rep stosb` for `memset()`")
Cc: stable@vger.kernel.org
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240725-arch-has-func-v1-1-5521ed354acd@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/string.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/include/nolibc/string.h b/tools/include/nolibc/string.h
index f9ab28421e6d..9ec9c24f38c0 100644
--- a/tools/include/nolibc/string.h
+++ b/tools/include/nolibc/string.h
@@ -7,6 +7,7 @@
 #ifndef _NOLIBC_STRING_H
 #define _NOLIBC_STRING_H
 
+#include "arch.h"
 #include "std.h"
 
 static void *malloc(size_t len);
-- 
cgit v1.2.3


From ae1f550efc11eaf1496c431d9c6e784cb49124c5 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Thu, 25 Jul 2024 19:10:44 +0200
Subject: tools/nolibc: add stdbool.h header
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

stdbool.h is very simple.
Provide an implementation for the user convenience.

Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240725-nolibc-stdbool-v1-1-a6ee2c80bcde@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/Makefile  |  1 +
 tools/include/nolibc/nolibc.h  |  3 ++-
 tools/include/nolibc/stdbool.h | 16 ++++++++++++++++
 3 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100644 tools/include/nolibc/stdbool.h

diff --git a/tools/include/nolibc/Makefile b/tools/include/nolibc/Makefile
index e69c26abe1ea..a1f55fb24bb3 100644
--- a/tools/include/nolibc/Makefile
+++ b/tools/include/nolibc/Makefile
@@ -35,6 +35,7 @@ all_files := \
 		stackprotector.h \
 		std.h \
 		stdarg.h \
+		stdbool.h \
 		stdint.h \
 		stdlib.h \
 		string.h \
diff --git a/tools/include/nolibc/nolibc.h b/tools/include/nolibc/nolibc.h
index 989e707263a4..92436b1e4441 100644
--- a/tools/include/nolibc/nolibc.h
+++ b/tools/include/nolibc/nolibc.h
@@ -74,7 +74,8 @@
  *            -I../nolibc -o hello hello.c -lgcc
  *
  * The available standard (but limited) include files are:
- *   ctype.h, errno.h, signal.h, stdarg.h, stdio.h, stdlib.h, string.h, time.h
+ *   ctype.h, errno.h, signal.h, stdarg.h, stdbool.h stdio.h, stdlib.h,
+ *   string.h, time.h
  *
  * In addition, the following ones are expected to be provided by the compiler:
  *   float.h, stddef.h
diff --git a/tools/include/nolibc/stdbool.h b/tools/include/nolibc/stdbool.h
new file mode 100644
index 000000000000..60feece22f17
--- /dev/null
+++ b/tools/include/nolibc/stdbool.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * Boolean types support for NOLIBC
+ * Copyright (C) 2024 Thomas Weißschuh <linux@weissschuh.net>
+ */
+
+#ifndef _NOLIBC_STDBOOL_H
+#define _NOLIBC_STDBOOL_H
+
+#define bool _Bool
+#define true 1
+#define false 0
+
+#define __bool_true_false_are_defined 1
+
+#endif /* _NOLIBC_STDBOOL_H */
-- 
cgit v1.2.3


From 754283ce8326fdce75d589c99cc58456199c123d Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Sun, 28 Jul 2024 22:34:11 +0200
Subject: tools/nolibc: pass argc, argv and envp to constructors
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Since 2005 glibc has passed argc, argv, and envp to all constructors.
As it is cheap and easy to do so, mirror that behaviour in nolibc.
This makes it easier to migrate applications to nolibc.

Link: https://lore.kernel.org/r/20240728-nolibc-constructor-args-v1-1-36d0bf5cd4c0@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/crt.h                   | 23 ++++++++++++-----------
 tools/testing/selftests/nolibc/nolibc-test.c |  5 +++--
 2 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/tools/include/nolibc/crt.h b/tools/include/nolibc/crt.h
index 43b551468c2a..ac291574f6c0 100644
--- a/tools/include/nolibc/crt.h
+++ b/tools/include/nolibc/crt.h
@@ -13,11 +13,11 @@ const unsigned long *_auxv __attribute__((weak));
 static void __stack_chk_init(void);
 static void exit(int);
 
-extern void (*const __preinit_array_start[])(void) __attribute__((weak));
-extern void (*const __preinit_array_end[])(void) __attribute__((weak));
+extern void (*const __preinit_array_start[])(int, char **, char**) __attribute__((weak));
+extern void (*const __preinit_array_end[])(int, char **, char**) __attribute__((weak));
 
-extern void (*const __init_array_start[])(void) __attribute__((weak));
-extern void (*const __init_array_end[])(void) __attribute__((weak));
+extern void (*const __init_array_start[])(int, char **, char**) __attribute__((weak));
+extern void (*const __init_array_end[])(int, char **, char**) __attribute__((weak));
 
 extern void (*const __fini_array_start[])(void) __attribute__((weak));
 extern void (*const __fini_array_end[])(void) __attribute__((weak));
@@ -29,7 +29,8 @@ void _start_c(long *sp)
 	char **argv;
 	char **envp;
 	int exitcode;
-	void (* const *func)(void);
+	void (* const *ctor_func)(int, char **, char **);
+	void (* const *dtor_func)(void);
 	const unsigned long *auxv;
 	/* silence potential warning: conflicting types for 'main' */
 	int _nolibc_main(int, char **, char **) __asm__ ("main");
@@ -66,16 +67,16 @@ void _start_c(long *sp)
 		;
 	_auxv = auxv;
 
-	for (func = __preinit_array_start; func < __preinit_array_end; func++)
-		(*func)();
-	for (func = __init_array_start; func < __init_array_end; func++)
-		(*func)();
+	for (ctor_func = __preinit_array_start; ctor_func < __preinit_array_end; ctor_func++)
+		(*ctor_func)(argc, argv, envp);
+	for (ctor_func = __init_array_start; ctor_func < __init_array_end; ctor_func++)
+		(*ctor_func)(argc, argv, envp);
 
 	/* go to application */
 	exitcode = _nolibc_main(argc, argv, envp);
 
-	for (func = __fini_array_end; func > __fini_array_start;)
-		(*--func)();
+	for (dtor_func = __fini_array_end; dtor_func > __fini_array_start;)
+		(*--dtor_func)();
 
 	exit(exitcode);
 }
diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 093d0512f4c5..0800b10fc3f7 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -686,9 +686,10 @@ static void constructor1(void)
 }
 
 __attribute__((constructor))
-static void constructor2(void)
+static void constructor2(int argc, char **argv, char **envp)
 {
-	constructor_test_value *= 2;
+	if (argc && argv && envp)
+		constructor_test_value *= 2;
 }
 
 int run_startup(int min, int max)
-- 
cgit v1.2.3


From 55850eb4e582f0696f40b8315ac31a45d6a4955e Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:37 +0200
Subject: tools/nolibc: arm: use clang-compatible asm syntax
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The clang assembler rejects the current syntax.
Switch to a syntax accepted by both GCC and clang.

Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-1-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-arm.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/include/nolibc/arch-arm.h b/tools/include/nolibc/arch-arm.h
index cae4afa7c1c7..d1c19d973e55 100644
--- a/tools/include/nolibc/arch-arm.h
+++ b/tools/include/nolibc/arch-arm.h
@@ -188,8 +188,8 @@
 void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
-		"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 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                          */
 	);
-- 
cgit v1.2.3


From 0daf8c86a45163f35b8d4f7795068c2511dd0ad9 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:38 +0200
Subject: tools/nolibc: mips: load current function to $t9
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

The MIPS calling convention requires the address of the current function
to be available in $t9.
This was not done so far.

For GCC this seems to have worked, but when compiled with clang the
executable segfault instantly.
Properly load the address of _start_c() into $t9 before calling it.

Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-2-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-mips.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/include/nolibc/arch-mips.h b/tools/include/nolibc/arch-mips.h
index 62cc50ef3288..a2ee77ed2fbb 100644
--- a/tools/include/nolibc/arch-mips.h
+++ b/tools/include/nolibc/arch-mips.h
@@ -194,7 +194,9 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
 		"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   _start_c\n"       /* transfer to c runtime                          */
+		"lui $t9, %hi(_start_c)\n" /* ABI requires current function address in $t9 */
+		"ori $t9, %lo(_start_c)\n"
+		"jalr $t9\n"             /* transfer to c runtime                          */
 		" nop\n"                 /* delayed slot                                   */
 		".set pop\n"
 	);
-- 
cgit v1.2.3


From 1daea158d0aae0770371f3079305a29fdb66829e Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:39 +0200
Subject: tools/nolibc: powerpc: limit stack-protector workaround to GCC
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

As mentioned in the comment, the workaround for
__attribute__((no_stack_protector)) is only necessary on GCC.
Avoid applying the workaround on clang, as clang does not recognize
__attribute__((__optimize__)) and would fail.

Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-3-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-powerpc.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/include/nolibc/arch-powerpc.h b/tools/include/nolibc/arch-powerpc.h
index ac212e6185b2..41ebd394b90c 100644
--- a/tools/include/nolibc/arch-powerpc.h
+++ b/tools/include/nolibc/arch-powerpc.h
@@ -172,7 +172,7 @@
 	_ret;                                                                \
 })
 
-#ifndef __powerpc64__
+#if !defined(__powerpc64__) && !defined(__clang__)
 /* FIXME: For 32-bit PowerPC, with newer gcc compilers (e.g. gcc 13.1.0),
  * "omit-frame-pointer" fails with __attribute__((no_stack_protector)) but
  * works with __attribute__((__optimize__("-fno-stack-protector")))
-- 
cgit v1.2.3


From 02a62b551cee585f7c2c93f54d1230d5714ff7d4 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:40 +0200
Subject: tools/nolibc: compiler: introduce __nolibc_has_attribute()
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

Recent compilers support __has_attribute() to check if a certain
compiler attribute is supported.
Unfortunately we have to first check if __has_attribute is supported in
the first place and then if a specific attribute is present.
These two checks can't be folded into a single condition as that would
lead to errors.

Nesting the two conditions like below works, but becomes ugly as soon
as #else blocks are used as those need to be duplicated for both levels
of #if.

    #if defined __has_attribute
    #  if __has_attribute (nonnull)
    #    define ATTR_NONNULL __attribute__ ((nonnull))
    #  endif
    #endif

Introduce a new helper which makes the usage of __has_attribute() nicer
and migrate the current user to it.

Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-4-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/compiler.h | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/tools/include/nolibc/compiler.h b/tools/include/nolibc/compiler.h
index beddc3665d69..1730d0454a55 100644
--- a/tools/include/nolibc/compiler.h
+++ b/tools/include/nolibc/compiler.h
@@ -6,20 +6,22 @@
 #ifndef _NOLIBC_COMPILER_H
 #define _NOLIBC_COMPILER_H
 
+#if defined(__has_attribute)
+#  define __nolibc_has_attribute(attr) __has_attribute(attr)
+#else
+#  define __nolibc_has_attribute(attr) 0
+#endif
+
 #if defined(__SSP__) || defined(__SSP_STRONG__) || defined(__SSP_ALL__) || defined(__SSP_EXPLICIT__)
 
 #define _NOLIBC_STACKPROTECTOR
 
 #endif /* defined(__SSP__) ... */
 
-#if defined(__has_attribute)
-#  if __has_attribute(no_stack_protector)
-#    define __no_stack_protector __attribute__((no_stack_protector))
-#  else
-#    define __no_stack_protector __attribute__((__optimize__("-fno-stack-protector")))
-#  endif
+#if __nolibc_has_attribute(no_stack_protector)
+#  define __no_stack_protector __attribute__((no_stack_protector))
 #else
 #  define __no_stack_protector __attribute__((__optimize__("-fno-stack-protector")))
-#endif /* defined(__has_attribute) */
+#endif /* __nolibc_has_attribute(no_stack_protector) */
 
 #endif /* _NOLIBC_COMPILER_H */
-- 
cgit v1.2.3


From ef32e9b6a325d1d013b30d898b4dff94082902cd Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:41 +0200
Subject: tools/nolibc: move entrypoint specifics to compiler.h
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The specific attributes for the _start entrypoint are duplicated for
each architecture.
Deduplicate it into a dedicated #define into compiler.h.

For clang compatibility, the epilogue will also need to be adapted, so
move that one, too.

Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-5-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-aarch64.h   | 4 ++--
 tools/include/nolibc/arch-arm.h       | 4 ++--
 tools/include/nolibc/arch-i386.h      | 4 ++--
 tools/include/nolibc/arch-loongarch.h | 4 ++--
 tools/include/nolibc/arch-mips.h      | 4 ++--
 tools/include/nolibc/arch-powerpc.h   | 4 ++--
 tools/include/nolibc/arch-riscv.h     | 4 ++--
 tools/include/nolibc/arch-s390.h      | 4 ++--
 tools/include/nolibc/arch-x86_64.h    | 4 ++--
 tools/include/nolibc/compiler.h       | 3 +++
 10 files changed, 21 insertions(+), 18 deletions(-)

diff --git a/tools/include/nolibc/arch-aarch64.h b/tools/include/nolibc/arch-aarch64.h
index b23ac1f04035..06fdef7b291a 100644
--- a/tools/include/nolibc/arch-aarch64.h
+++ b/tools/include/nolibc/arch-aarch64.h
@@ -142,13 +142,13 @@
 })
 
 /* startup code */
-void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
 {
 	__asm__ volatile (
 		"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();
+	__nolibc_entrypoint_epilogue();
 }
 #endif /* _NOLIBC_ARCH_AARCH64_H */
diff --git a/tools/include/nolibc/arch-arm.h b/tools/include/nolibc/arch-arm.h
index d1c19d973e55..6180ff99ab43 100644
--- a/tools/include/nolibc/arch-arm.h
+++ b/tools/include/nolibc/arch-arm.h
@@ -185,7 +185,7 @@
 })
 
 /* startup code */
-void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
 {
 	__asm__ volatile (
 		"mov r0, sp\n"          /* save stack pointer to %r0, as arg1 of _start_c */
@@ -193,7 +193,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
 		"mov sp, ip\n"
 		"bl  _start_c\n"        /* transfer to c runtime                          */
 	);
-	__builtin_unreachable();
+	__nolibc_entrypoint_epilogue();
 }
 
 #endif /* _NOLIBC_ARCH_ARM_H */
diff --git a/tools/include/nolibc/arch-i386.h b/tools/include/nolibc/arch-i386.h
index 28c26a00a762..ff5afc35bbd8 100644
--- a/tools/include/nolibc/arch-i386.h
+++ b/tools/include/nolibc/arch-i386.h
@@ -162,7 +162,7 @@
  * 2) The deepest stack frame should be set to zero
  *
  */
-void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
 {
 	__asm__ volatile (
 		"xor  %ebp, %ebp\n"       /* zero the stack frame                                */
@@ -174,7 +174,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
 		"call _start_c\n"         /* transfer to c runtime                               */
 		"hlt\n"                   /* ensure it does not return                           */
 	);
-	__builtin_unreachable();
+	__nolibc_entrypoint_epilogue();
 }
 
 #endif /* _NOLIBC_ARCH_I386_H */
diff --git a/tools/include/nolibc/arch-loongarch.h b/tools/include/nolibc/arch-loongarch.h
index 3f8ef8f86c0f..fb519545959e 100644
--- a/tools/include/nolibc/arch-loongarch.h
+++ b/tools/include/nolibc/arch-loongarch.h
@@ -149,14 +149,14 @@
 #endif
 
 /* startup code */
-void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
 {
 	__asm__ volatile (
 		"move          $a0, $sp\n"         /* save stack pointer to $a0, as arg1 of _start_c */
 		LONG_BSTRINS " $sp, $zero, 3, 0\n" /* $sp must be 16-byte aligned                    */
 		"bl            _start_c\n"         /* transfer to c runtime                          */
 	);
-	__builtin_unreachable();
+	__nolibc_entrypoint_epilogue();
 }
 
 #endif /* _NOLIBC_ARCH_LOONGARCH_H */
diff --git a/tools/include/nolibc/arch-mips.h b/tools/include/nolibc/arch-mips.h
index a2ee77ed2fbb..1791a8ce58da 100644
--- a/tools/include/nolibc/arch-mips.h
+++ b/tools/include/nolibc/arch-mips.h
@@ -179,7 +179,7 @@
 })
 
 /* startup code, note that it's called __start on MIPS */
-void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector __start(void)
+void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector __start(void)
 {
 	__asm__ volatile (
 		".set push\n"
@@ -200,7 +200,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
 		" nop\n"                 /* delayed slot                                   */
 		".set pop\n"
 	);
-	__builtin_unreachable();
+	__nolibc_entrypoint_epilogue();
 }
 
 #endif /* _NOLIBC_ARCH_MIPS_H */
diff --git a/tools/include/nolibc/arch-powerpc.h b/tools/include/nolibc/arch-powerpc.h
index 41ebd394b90c..ee2fdb8d601d 100644
--- a/tools/include/nolibc/arch-powerpc.h
+++ b/tools/include/nolibc/arch-powerpc.h
@@ -184,7 +184,7 @@
 #endif /* !__powerpc64__ */
 
 /* startup code */
-void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
 {
 #ifdef __powerpc64__
 #if _CALL_ELF == 2
@@ -215,7 +215,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
 		"bl     _start_c\n"     /* transfer to c runtime                         */
 	);
 #endif
-	__builtin_unreachable();
+	__nolibc_entrypoint_epilogue();
 }
 
 #endif /* _NOLIBC_ARCH_POWERPC_H */
diff --git a/tools/include/nolibc/arch-riscv.h b/tools/include/nolibc/arch-riscv.h
index 1927c643c739..8827bf936212 100644
--- a/tools/include/nolibc/arch-riscv.h
+++ b/tools/include/nolibc/arch-riscv.h
@@ -140,7 +140,7 @@
 })
 
 /* startup code */
-void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
 {
 	__asm__ volatile (
 		".option push\n"
@@ -151,7 +151,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
 		"andi sp, a0, -16\n"      /* sp must be 16-byte aligned                    */
 		"call _start_c\n"         /* transfer to c runtime                         */
 	);
-	__builtin_unreachable();
+	__nolibc_entrypoint_epilogue();
 }
 
 #endif /* _NOLIBC_ARCH_RISCV_H */
diff --git a/tools/include/nolibc/arch-s390.h b/tools/include/nolibc/arch-s390.h
index 5d60fd43f883..2ec13d8b9a2d 100644
--- a/tools/include/nolibc/arch-s390.h
+++ b/tools/include/nolibc/arch-s390.h
@@ -139,7 +139,7 @@
 })
 
 /* startup code */
-void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
 {
 	__asm__ volatile (
 		"lgr	%r2, %r15\n"          /* save stack pointer to %r2, as arg1 of _start_c */
@@ -147,7 +147,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
 		"xc	0(8,%r15), 0(%r15)\n" /* clear backchain                                */
 		"brasl	%r14, _start_c\n"     /* transfer to c runtime                          */
 	);
-	__builtin_unreachable();
+	__nolibc_entrypoint_epilogue();
 }
 
 struct s390_mmap_arg_struct {
diff --git a/tools/include/nolibc/arch-x86_64.h b/tools/include/nolibc/arch-x86_64.h
index 68609f421934..65252c005a30 100644
--- a/tools/include/nolibc/arch-x86_64.h
+++ b/tools/include/nolibc/arch-x86_64.h
@@ -161,7 +161,7 @@
  * 2) The deepest stack frame should be zero (the %rbp).
  *
  */
-void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
+void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
 {
 	__asm__ volatile (
 		"xor  %ebp, %ebp\n"       /* zero the stack frame                            */
@@ -170,7 +170,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
 		"call _start_c\n"         /* transfer to c runtime                           */
 		"hlt\n"                   /* ensure it does not return                       */
 	);
-	__builtin_unreachable();
+	__nolibc_entrypoint_epilogue();
 }
 
 #define NOLIBC_ARCH_HAS_MEMMOVE
diff --git a/tools/include/nolibc/compiler.h b/tools/include/nolibc/compiler.h
index 1730d0454a55..3a1d5b8d4fb9 100644
--- a/tools/include/nolibc/compiler.h
+++ b/tools/include/nolibc/compiler.h
@@ -12,6 +12,9 @@
 #  define __nolibc_has_attribute(attr) 0
 #endif
 
+#define __nolibc_entrypoint __attribute__((optimize("Os", "omit-frame-pointer")))
+#define __nolibc_entrypoint_epilogue() __builtin_unreachable()
+
 #if defined(__SSP__) || defined(__SSP_STRONG__) || defined(__SSP_ALL__) || defined(__SSP_EXPLICIT__)
 
 #define _NOLIBC_STACKPROTECTOR
-- 
cgit v1.2.3


From e098eebb63cb1c03813559b5db9da4451ba3a318 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:42 +0200
Subject: tools/nolibc: compiler: use attribute((naked)) if available
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The current entrypoint attributes optimize("Os", "omit-frame-pointer")
are intended to avoid all compiler generated code, like function
porologue and epilogue.
This is the exact usecase implemented by the attribute "naked".

Unfortunately this is not implemented by GCC for all targets,
so only use it where available.
This also provides compatibility with clang, which recognizes the
"naked" attribute but not the previously used attribute "optimized".

Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-6-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/compiler.h | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/tools/include/nolibc/compiler.h b/tools/include/nolibc/compiler.h
index 3a1d5b8d4fb9..9bc6a706a332 100644
--- a/tools/include/nolibc/compiler.h
+++ b/tools/include/nolibc/compiler.h
@@ -12,8 +12,13 @@
 #  define __nolibc_has_attribute(attr) 0
 #endif
 
-#define __nolibc_entrypoint __attribute__((optimize("Os", "omit-frame-pointer")))
-#define __nolibc_entrypoint_epilogue() __builtin_unreachable()
+#if __nolibc_has_attribute(naked)
+#  define __nolibc_entrypoint __attribute__((naked))
+#  define __nolibc_entrypoint_epilogue()
+#else
+#  define __nolibc_entrypoint __attribute__((optimize("Os", "omit-frame-pointer")))
+#  define __nolibc_entrypoint_epilogue() __builtin_unreachable()
+#endif /* __nolibc_has_attribute(naked) */
 
 #if defined(__SSP__) || defined(__SSP_STRONG__) || defined(__SSP_ALL__) || defined(__SSP_EXPLICIT__)
 
-- 
cgit v1.2.3


From ddae1d7fab8c5dc5d12da120dc410c4f374d37c3 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:43 +0200
Subject: selftests/nolibc: report failure if no testcase passed
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

When nolibc-test is so broken, it doesn't even start,
don't report success.

Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-7-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 3fbabab46958..46dfbb50fae5 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -157,7 +157,7 @@ LDFLAGS :=
 
 REPORT  ?= awk '/\[OK\][\r]*$$/{p++} /\[FAIL\][\r]*$$/{if (!f) printf("\n"); f++; print;} /\[SKIPPED\][\r]*$$/{s++} \
 		END{ printf("\n%3d test(s): %3d passed, %3d skipped, %3d failed => status: ", p+s+f, p, s, f); \
-		if (f) printf("failure\n"); else if (s) printf("warning\n"); else printf("success\n");; \
+		if (f || !p) printf("failure\n"); else if (s) printf("warning\n"); else printf("success\n");; \
 		printf("\nSee all results in %s\n", ARGV[1]); }'
 
 help:
-- 
cgit v1.2.3


From f1a58f61d88642ae1e6e97e9d72d73bc70a93cb8 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:44 +0200
Subject: selftests/nolibc: avoid passing NULL to printf("%s")
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Clang on higher optimization levels detects that NULL is passed to
printf("%s") and warns about it.
While printf() from nolibc gracefully handles that NULL,
it is undefined behavior as per POSIX, so the warning is reasonable.
Avoid the warning by transforming NULL into a non-NULL placeholder.

Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-8-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/nolibc-test.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 0800b10fc3f7..6fba7025c5e3 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -542,7 +542,7 @@ int expect_strzr(const char *expr, int llen)
 {
 	int ret = 0;
 
-	llen += printf(" = <%s> ", expr);
+	llen += printf(" = <%s> ", expr ? expr : "(null)");
 	if (expr) {
 		ret = 1;
 		result(llen, FAIL);
@@ -561,7 +561,7 @@ int expect_strnz(const char *expr, int llen)
 {
 	int ret = 0;
 
-	llen += printf(" = <%s> ", expr);
+	llen += printf(" = <%s> ", expr ? expr : "(null)");
 	if (!expr) {
 		ret = 1;
 		result(llen, FAIL);
-- 
cgit v1.2.3


From 1a1200b66fd52dca33255270a09a093592c3b877 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:45 +0200
Subject: selftests/nolibc: determine $(srctree) first
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The nolibc-test Makefile includes various other Makefiles from the tree.
At first these are included with relative paths like
"../../../build/Build.include" but as soon as $(srctree) is set up,
the inclusions use that instead to build full paths.

To keep the style of inclusions consistent, perform the setup
$(srctree) as early as possible and use it for all inclusions.

Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-9-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/Makefile | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 46dfbb50fae5..803a4e1bbe24 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -1,9 +1,14 @@
 # SPDX-License-Identifier: GPL-2.0
 # Makefile for nolibc tests
-include ../../../scripts/Makefile.include
-include ../../../scripts/utilities.mak
+# we're in ".../tools/testing/selftests/nolibc"
+ifeq ($(srctree),)
+srctree := $(patsubst %/tools/testing/selftests/,%,$(dir $(CURDIR)))
+endif
+
+include $(srctree)/tools/scripts/Makefile.include
+include $(srctree)/tools/scripts/utilities.mak
 # We need this for the "cc-option" macro.
-include ../../../build/Build.include
+include $(srctree)/tools/build/Build.include
 
 ifneq ($(O),)
 ifneq ($(call is-absolute,$(O)),y)
@@ -11,11 +16,6 @@ $(error Only absolute O= parameters are supported)
 endif
 endif
 
-# we're in ".../tools/testing/selftests/nolibc"
-ifeq ($(srctree),)
-srctree := $(patsubst %/tools/testing/selftests/,%,$(dir $(CURDIR)))
-endif
-
 ifeq ($(ARCH),)
 include $(srctree)/scripts/subarch.include
 ARCH = $(SUBARCH)
-- 
cgit v1.2.3


From ae574ae37059da67b90916f14b482bbce0c0ab01 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:46 +0200
Subject: selftests/nolibc: add support for LLVM= parameter
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Makefile.include can modify CC and CFLAGS for usage with clang.
Make use of it.

Makefile.include is currently used to handle the O= variable.
This is incompatible with the LLVM= handling as for O= it has to be
included as early as possible, while for LLVM= it needs to be included
after CFLAGS are set up.

To avoid this incompatibility, switch the O= handling to custom logic.

Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-10-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/Makefile | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 803a4e1bbe24..cdff317c35f2 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -5,7 +5,6 @@ ifeq ($(srctree),)
 srctree := $(patsubst %/tools/testing/selftests/,%,$(dir $(CURDIR)))
 endif
 
-include $(srctree)/tools/scripts/Makefile.include
 include $(srctree)/tools/scripts/utilities.mak
 # We need this for the "cc-option" macro.
 include $(srctree)/tools/build/Build.include
@@ -14,6 +13,9 @@ ifneq ($(O),)
 ifneq ($(call is-absolute,$(O)),y)
 $(error Only absolute O= parameters are supported)
 endif
+objtree := $(O)
+else
+objtree ?= $(srctree)
 endif
 
 ifeq ($(ARCH),)
@@ -21,8 +23,6 @@ include $(srctree)/scripts/subarch.include
 ARCH = $(SUBARCH)
 endif
 
-objtree ?= $(srctree)
-
 # XARCH extends the kernel's ARCH with a few variants of the same
 # architecture that only differ by the configuration, the toolchain
 # and the Qemu program used. It is copied as-is into ARCH except for
@@ -155,6 +155,9 @@ CFLAGS  ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 -W -Wall -Wex
 		$(CFLAGS_$(XARCH)) $(CFLAGS_STACKPROTECTOR) $(CFLAGS_EXTRA)
 LDFLAGS :=
 
+# Modify CFLAGS based on LLVM=
+include $(srctree)/tools/scripts/Makefile.include
+
 REPORT  ?= awk '/\[OK\][\r]*$$/{p++} /\[FAIL\][\r]*$$/{if (!f) printf("\n"); f++; print;} /\[SKIPPED\][\r]*$$/{s++} \
 		END{ printf("\n%3d test(s): %3d passed, %3d skipped, %3d failed => status: ", p+s+f, p, s, f); \
 		if (f || !p) printf("failure\n"); else if (s) printf("warning\n"); else printf("success\n");; \
-- 
cgit v1.2.3


From 1bd75aeb5446eb2b1351465e88a98fd784003250 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:47 +0200
Subject: selftests/nolibc: add cc-option compatible with clang cross builds
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The cc-option macro from Build.include is not compatible with clang
cross builds, as it does not respect the "--target" and similar flags,
set up by Mekfile.include.

Provide a custom variant which works correctly.

Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-11-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/Makefile | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index cdff317c35f2..b8577086e008 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -6,8 +6,8 @@ srctree := $(patsubst %/tools/testing/selftests/,%,$(dir $(CURDIR)))
 endif
 
 include $(srctree)/tools/scripts/utilities.mak
-# We need this for the "cc-option" macro.
-include $(srctree)/tools/build/Build.include
+# We need this for the "__cc-option" macro.
+include $(srctree)/scripts/Makefile.compiler
 
 ifneq ($(O),)
 ifneq ($(call is-absolute,$(O)),y)
@@ -23,6 +23,8 @@ include $(srctree)/scripts/subarch.include
 ARCH = $(SUBARCH)
 endif
 
+cc-option = $(call __cc-option, $(CC),$(CLANG_CROSS_FLAGS),$(1),$(2))
+
 # XARCH extends the kernel's ARCH with a few variants of the same
 # architecture that only differ by the configuration, the toolchain
 # and the Qemu program used. It is copied as-is into ARCH except for
-- 
cgit v1.2.3


From 27e458bbebdb0aa2aecce86d22c7f02b66e68ee1 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:48 +0200
Subject: selftests/nolibc: run-tests.sh: avoid overwriting CFLAGS_EXTRA
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

If the user specified their own CFLAGS_EXTRA these should not be
overwritten by `-e`.

Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-12-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/run-tests.sh | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/nolibc/run-tests.sh b/tools/testing/selftests/nolibc/run-tests.sh
index 0446e6326a40..324509b99e2c 100755
--- a/tools/testing/selftests/nolibc/run-tests.sh
+++ b/tools/testing/selftests/nolibc/run-tests.sh
@@ -15,7 +15,7 @@ download_location="${cache_dir}/crosstools/"
 build_location="$(realpath "${cache_dir}"/nolibc-tests/)"
 perform_download=0
 test_mode=system
-CFLAGS_EXTRA="-Werror"
+werror=1
 archs="i386 x86_64 arm64 arm mips32le mips32be ppc ppc64 ppc64le riscv s390 loongarch"
 
 TEMP=$(getopt -o 'j:d:c:b:a:m:peh' -n "$0" -- "$@")
@@ -69,7 +69,7 @@ while true; do
 			test_mode="$2"
 			shift 2; continue ;;
 		'-e')
-			CFLAGS_EXTRA=""
+			werror=0
 			shift; continue ;;
 		'-h')
 			print_usage
@@ -140,6 +140,9 @@ test_arch() {
 	ct_abi=$(crosstool_abi "$1")
 	cross_compile=$(realpath "${download_location}gcc-${crosstool_version}-nolibc/${ct_arch}-${ct_abi}/bin/${ct_arch}-${ct_abi}-")
 	build_dir="${build_location}/${arch}"
+	if [ "$werror" -ne 0 ]; then
+		CFLAGS_EXTRA="$CFLAGS_EXTRA -Werror"
+	fi
 	MAKE=(make -j"${nproc}" XARCH="${arch}" CROSS_COMPILE="${cross_compile}" O="${build_dir}")
 
 	mkdir -p "$build_dir"
-- 
cgit v1.2.3


From 801cf69ca03040a75ed73be263aa6f0fdcb8af5d Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:49 +0200
Subject: selftests/nolibc: don't use libgcc when building with clang
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The logic in clang to find the libgcc.a from a GCC toolchain for a
specific ABI does not work reliably and can lead to errors.
Instead disable libgcc when building with clang, as it's not needed
anyways.

Acked-by: Willy Tarreau <w@1wt.eu>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-13-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/Makefile | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index b8577086e008..f0ce8264baac 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -157,6 +157,13 @@ CFLAGS  ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 -W -Wall -Wex
 		$(CFLAGS_$(XARCH)) $(CFLAGS_STACKPROTECTOR) $(CFLAGS_EXTRA)
 LDFLAGS :=
 
+LIBGCC := -lgcc
+
+ifneq ($(LLVM),)
+# Not needed for clang
+LIBGCC :=
+endif
+
 # Modify CFLAGS based on LLVM=
 include $(srctree)/tools/scripts/Makefile.include
 
@@ -209,11 +216,11 @@ sysroot/$(ARCH)/include:
 ifneq ($(NOLIBC_SYSROOT),0)
 nolibc-test: nolibc-test.c nolibc-test-linkage.c sysroot/$(ARCH)/include
 	$(QUIET_CC)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ \
-	  -nostdlib -nostdinc -static -Isysroot/$(ARCH)/include nolibc-test.c nolibc-test-linkage.c -lgcc
+	  -nostdlib -nostdinc -static -Isysroot/$(ARCH)/include nolibc-test.c nolibc-test-linkage.c $(LIBGCC)
 else
 nolibc-test: nolibc-test.c nolibc-test-linkage.c
 	$(QUIET_CC)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ \
-	  -nostdlib -static -include $(srctree)/tools/include/nolibc/nolibc.h nolibc-test.c nolibc-test-linkage.c -lgcc
+	  -nostdlib -static -include $(srctree)/tools/include/nolibc/nolibc.h nolibc-test.c nolibc-test-linkage.c $(LIBGCC)
 endif
 
 libc-test: nolibc-test.c nolibc-test-linkage.c
-- 
cgit v1.2.3


From 8404af7e13eeef91d0e69b44214cbafc2767b7f2 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:50 +0200
Subject: selftests/nolibc: use correct clang target for s390/systemz
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The target names between GCC and clang differ for s390.
While GCC uses "s390", clang uses "systemz".
This mapping is not handled by tools/scripts/Makefile.include,
so do it in the nolibc-test Makefile.

Acked-by: Willy Tarreau <w@1wt.eu>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-14-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index f0ce8264baac..8de98ea7af80 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -167,6 +167,9 @@ endif
 # Modify CFLAGS based on LLVM=
 include $(srctree)/tools/scripts/Makefile.include
 
+# GCC uses "s390", clang "systemz"
+CLANG_CROSS_FLAGS := $(subst --target=s390-linux,--target=systemz-linux,$(CLANG_CROSS_FLAGS))
+
 REPORT  ?= awk '/\[OK\][\r]*$$/{p++} /\[FAIL\][\r]*$$/{if (!f) printf("\n"); f++; print;} /\[SKIPPED\][\r]*$$/{s++} \
 		END{ printf("\n%3d test(s): %3d passed, %3d skipped, %3d failed => status: ", p+s+f, p, s, f); \
 		if (f || !p) printf("failure\n"); else if (s) printf("warning\n"); else printf("success\n");; \
-- 
cgit v1.2.3


From 22ba81c50a49468d80055674d8d6f78afb1c92c4 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Wed, 7 Aug 2024 23:51:51 +0200
Subject: selftests/nolibc: run-tests.sh: allow building through LLVM
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The nolibc tests can now be properly built with LLVM.
Expose this through run-tests.sh.

Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-15-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/run-tests.sh | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/nolibc/run-tests.sh b/tools/testing/selftests/nolibc/run-tests.sh
index 324509b99e2c..e7ecda4ae796 100755
--- a/tools/testing/selftests/nolibc/run-tests.sh
+++ b/tools/testing/selftests/nolibc/run-tests.sh
@@ -16,9 +16,10 @@ build_location="$(realpath "${cache_dir}"/nolibc-tests/)"
 perform_download=0
 test_mode=system
 werror=1
+llvm=
 archs="i386 x86_64 arm64 arm mips32le mips32be ppc ppc64 ppc64le riscv s390 loongarch"
 
-TEMP=$(getopt -o 'j:d:c:b:a:m:peh' -n "$0" -- "$@")
+TEMP=$(getopt -o 'j:d:c:b:a:m:pelh' -n "$0" -- "$@")
 
 eval set -- "$TEMP"
 unset TEMP
@@ -42,6 +43,7 @@ Options:
  -b [DIR]       Build location (default: ${build_location})
  -m [MODE]      Test mode user/system (default: ${test_mode})
  -e             Disable -Werror
+ -l             Build with LLVM/clang
 EOF
 }
 
@@ -71,6 +73,9 @@ while true; do
 		'-e')
 			werror=0
 			shift; continue ;;
+		'-l')
+			llvm=1
+			shift; continue ;;
 		'-h')
 			print_usage
 			exit 0
@@ -143,7 +148,7 @@ test_arch() {
 	if [ "$werror" -ne 0 ]; then
 		CFLAGS_EXTRA="$CFLAGS_EXTRA -Werror"
 	fi
-	MAKE=(make -j"${nproc}" XARCH="${arch}" CROSS_COMPILE="${cross_compile}" O="${build_dir}")
+	MAKE=(make -j"${nproc}" XARCH="${arch}" CROSS_COMPILE="${cross_compile}" LLVM="${llvm}" O="${build_dir}")
 
 	mkdir -p "$build_dir"
 	if [ "$test_mode" = "system" ] && [ ! -f "${build_dir}/.config" ]; then
-- 
cgit v1.2.3


From 0021d6670d1a997549a39bf629da9940bf4068ed Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Mon, 12 Aug 2024 22:50:17 +0200
Subject: tools/nolibc: crt: mark _start_c() as used
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

During LTO the reference from the asm startup code to the _start_c()
function is not visible and _start_c() is removed.
This will then lead to errors during linking.
As _start_c() is indeed always used, mark it as such.

Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240812-nolibc-lto-v2-1-736af7bbefa8@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/crt.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/include/nolibc/crt.h b/tools/include/nolibc/crt.h
index ac291574f6c0..bbcd5fd09806 100644
--- a/tools/include/nolibc/crt.h
+++ b/tools/include/nolibc/crt.h
@@ -22,7 +22,7 @@ extern void (*const __init_array_end[])(int, char **, char**) __attribute__((wea
 extern void (*const __fini_array_start[])(void) __attribute__((weak));
 extern void (*const __fini_array_end[])(void) __attribute__((weak));
 
-__attribute__((weak))
+__attribute__((weak,used))
 void _start_c(long *sp)
 {
 	long argc;
-- 
cgit v1.2.3


From ff7b9abbfce985b92f71c855246508edb0980cd6 Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Mon, 12 Aug 2024 22:50:18 +0200
Subject: tools/nolibc: stackprotector: mark implicitly used symbols as used
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

During LTO the references from the compiler-generated prologue and
epilogues to the stack protector symbols are not visible and the symbols
are removed.
This will then lead to errors during linking.
As those symbols are already #ifdeffed-out if unused mark them as "used"
to prevent their removal.

Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240812-nolibc-lto-v2-2-736af7bbefa8@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/stackprotector.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/include/nolibc/stackprotector.h b/tools/include/nolibc/stackprotector.h
index 13f1d0e60387..1d0d5259ec41 100644
--- a/tools/include/nolibc/stackprotector.h
+++ b/tools/include/nolibc/stackprotector.h
@@ -18,7 +18,7 @@
  * triggering stack protector errors themselves
  */
 
-__attribute__((weak,noreturn,section(".text.nolibc_stack_chk")))
+__attribute__((weak,used,noreturn,section(".text.nolibc_stack_chk")))
 void __stack_chk_fail(void)
 {
 	pid_t pid;
@@ -34,7 +34,7 @@ void __stack_chk_fail_local(void)
 	__stack_chk_fail();
 }
 
-__attribute__((weak,section(".data.nolibc_stack_chk")))
+__attribute__((weak,used,section(".data.nolibc_stack_chk")))
 uintptr_t __stack_chk_guard;
 
 static __no_stack_protector void __stack_chk_init(void)
-- 
cgit v1.2.3


From 25fb329a23c78d59a055a7b1329d18f30a2be92d Mon Sep 17 00:00:00 2001
From: Thomas Weißschuh <linux@weissschuh.net>
Date: Mon, 12 Aug 2024 22:50:19 +0200
Subject: tools/nolibc: x86_64: use local label in memcpy/memmove
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Compiling arch-x86_64.h with clang and binutils LD yields
duplicate label errors:

.../gcc-13.2.0-nolibc/x86_64-linux/bin/x86_64-linux-ld: error: LLVM gold plugin: <inline asm>:44:1: symbol '.Lbackward_copy' is already defined
.Lbackward_copy:leaq -1(%rdi, %rcx, 1), %rdi

Instead of a local symbol use a local label which can be defined
multiple times and therefore avoids the error.

Reviewed-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240812-nolibc-lto-v2-3-736af7bbefa8@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-x86_64.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/include/nolibc/arch-x86_64.h b/tools/include/nolibc/arch-x86_64.h
index 65252c005a30..1e40620a2b33 100644
--- a/tools/include/nolibc/arch-x86_64.h
+++ b/tools/include/nolibc/arch-x86_64.h
@@ -193,10 +193,10 @@ __asm__ (
 	"movq %rdi, %rdx\n\t"
 	"subq %rsi, %rdx\n\t"
 	"cmpq %rcx, %rdx\n\t"
-	"jb   .Lbackward_copy\n\t"
+	"jb   1f\n\t"
 	"rep movsb\n\t"
 	"retq\n"
-".Lbackward_copy:"
+"1:" /* backward copy */
 	"leaq -1(%rdi, %rcx, 1), %rdi\n\t"
 	"leaq -1(%rsi, %rcx, 1), %rsi\n\t"
 	"std\n\t"
-- 
cgit v1.2.3