kbuild: require gcc-8 and binutils-2.30

Commit a3e8fe814ad1 ("x86/build: Raise the minimum GCC version to 8.1")
raised the minimum compiler version as enforced by Kbuild to gcc-8.1
and clang-15 for x86.

This is actually the same gcc version that has been discussed as the
minimum for all architectures several times in the past, with little
objection. A previous concern was the kernel for SLE15-SP7 needing to
be built with gcc-7. As this ended up still using linux-6.4 and there
is no plan for an SP8, this is no longer a problem.

Change it for all architectures and adjust the documentation accordingly.
A few version checks can be removed in the process. The binutils
version 2.30 is the lowest version used in combination with gcc-8 on
common distros, so use that as the corresponding minimum.

Link: https://lore.kernel.org/lkml/[e-mail]/
Link: https://lore.kernel.org/lkml/[e-mail]/
Acked-by: Mark Rutland <[e-mail]>
Signed-off-by: Arnd Bergmann <[e-mail]>

Documentation/admin-guide/README.rst

···
 Compiling the kernel
 --------------------
 
- - Make sure you have at least gcc 5.1 available.
+ - Make sure you have at least gcc 8.1 available.
    For more information, refer to :ref:`Documentation/process/changes.rst <changes>`.
 
  - Do a ``make`` to create a compressed kernel image. It is also possible to do

Documentation/kbuild/makefiles.rst

···
 
   Example::
 
-    cflags-$(call gcc-min-version, 70100) := -foo
+    cflags-$(call gcc-min-version, 110100) := -foo
 
   In this example, cflags-y will be assigned the value -foo if $(CC) is gcc and
-  $(CONFIG_GCC_VERSION) is >= 7.1.
+  $(CONFIG_GCC_VERSION) is >= 11.1.
 
 clang-min-version
   clang-min-version tests if the value of $(CONFIG_CLANG_VERSION) is greater

Documentation/process/changes.rst

···
 ====================== ===============  ========================================
         Program        Minimal version       Command to check the version
 ====================== ===============  ========================================
-GNU C                  5.1              gcc --version
+GNU C                  8.1              gcc --version
 Clang/LLVM (optional)  13.0.1           clang --version
 Rust (optional)        1.78.0           rustc --version
 bindgen (optional)     0.65.1           bindgen --version
 GNU make               4.0              make --version
 bash                   4.2              bash --version
-binutils               2.25             ld -v
+binutils               2.30             ld -v
 flex                   2.5.35           flex --version
 bison                  2.0              bison --version
 pahole                 1.16             pahole --version

Documentation/translations/it_IT/process/changes.rst

···
 ====================== =================  ========================================
         Programma       Versione minima       Comando per verificare la versione
 ====================== =================  ========================================
-GNU C                  5.1                gcc --version
+GNU C                  8.1                gcc --version
 Clang/LLVM (optional)  13.0.0             clang --version
 Rust (opzionale)       1.78.0             rustc --version
 bindgen (opzionale)    0.65.1             bindgen --version
 GNU make               4.0                make --version
 bash                   4.2                bash --version
-binutils               2.25               ld -v
+binutils               2.30               ld -v
 flex                   2.5.35             flex --version
 bison                  2.0                bison --version
 pahole                 1.16               pahole --version

Documentation/translations/zh_CN/admin-guide/README.rst

···
 编译内核
 ---------
 
- - 确保您至少有gcc 5.1可用。
+ - 确保您至少有gcc 8.1可用。
    有关更多信息，请参阅 :ref:`Documentation/process/changes.rst <changes>` 。
 
  - 执行 ``make`` 来创建压缩内核映像。如果您安装了lilo以适配内核makefile，

arch/um/Makefile

···
 	$(Q)$(MAKE) $(build)=$(HOST_DIR)/um include/generated/user_constants.h
 
 LINK-$(CONFIG_LD_SCRIPT_STATIC) += -static
-ifdef CONFIG_LD_SCRIPT_DYN
-LINK-$(call gcc-min-version, 60100)$(CONFIG_CC_IS_CLANG) += -no-pie
-endif
+LINK-$(CONFIG_LD_SCRIPT_DYN) += -no-pie
 LINK-$(CONFIG_LD_SCRIPT_DYN_RPATH) += -Wl,-rpath,/lib
 
 CFLAGS_NO_HARDENING := $(call cc-option, -fno-PIC,) $(call cc-option, -fno-pic,) \

include/linux/unroll.h

···
 
 #ifdef CONFIG_CC_IS_CLANG
 #define __pick_unrolled(x, y)		_Pragma(#x)
-#elif CONFIG_GCC_VERSION >= 80000
-#define __pick_unrolled(x, y)		_Pragma(#y)
 #else
-#define __pick_unrolled(x, y)		/* not supported */
+#define __pick_unrolled(x, y)		_Pragma(#y)
 #endif
 
 /**

kernel/gcov/gcc_4_7.c

···
 #define GCOV_COUNTERS			9
 #elif (__GNUC__ >= 10)
 #define GCOV_COUNTERS			8
-#elif (__GNUC__ >= 7)
-#define GCOV_COUNTERS			9
-#elif (__GNUC__ > 5) || (__GNUC__ == 5 && __GNUC_MINOR__ >= 1)
-#define GCOV_COUNTERS			10
 #else
 #define GCOV_COUNTERS			9
 #endif

lib/test_fortify/Makefile

···
 $(obj)/test_fortify.log: $(addprefix $(obj)/, $(logs)) FORCE
 	$(call if_changed,gen_fortify_log)
 
-# GCC<=7 does not always produce *.d files.
-# Run the tests only for GCC>=8 or Clang.
-always-$(call gcc-min-version, 80000) += test_fortify.log
-always-$(CONFIG_CC_IS_CLANG)          += test_fortify.log
+always-y += test_fortify.log
 
 # Some architectures define __NO_FORTIFY if __SANITIZE_ADDRESS__ is undefined.
 # Pass CFLAGS_KASAN to avoid warnings.

scripts/Makefile.compiler

···
 cc-disable-warning = $(if $(call cc-option,-W$(strip $1)),-Wno-$(strip $1))
 
 # gcc-min-version
-# Usage: cflags-$(call gcc-min-version, 70100) += -foo
+# Usage: cflags-$(call gcc-min-version, 110100) += -foo
 gcc-min-version = $(call test-ge, $(CONFIG_GCC_VERSION), $1)
 
 # clang-min-version

scripts/gcc-plugins/gcc-common.h

···
 #define GCC_COMMON_H_INCLUDED
 
 #include "bversion.h"
-#if BUILDING_GCC_VERSION >= 6000
 #include "gcc-plugin.h"
-#else
-#include "plugin.h"
-#endif
 #include "plugin-version.h"
 #include "config.h"
 #include "system.h"
···
 
 #include "hash-map.h"
 
-#if BUILDING_GCC_VERSION >= 7000
 #include "memmodel.h"
-#endif
 #include "emit-rtl.h"
 #include "debug.h"
 #include "target.h"
···
 #include "context.h"
 #include "tree-ssa-alias.h"
 #include "tree-ssa.h"
-#if BUILDING_GCC_VERSION >= 7000
 #include "tree-vrp.h"
-#endif
 #include "tree-ssanames.h"
 #include "print-tree.h"
 #include "tree-eh.h"
···
 	return g->get_passes()->get_pass_for_id(id);
 }
 
-#if BUILDING_GCC_VERSION < 6000
-/* gimple related */
-template <>
-template <>
-inline bool is_a_helper<const gassign *>::test(const_gimple gs)
-{
-	return gs->code == GIMPLE_ASSIGN;
-}
-#endif
-
 #define TODO_verify_ssa TODO_verify_il
 #define TODO_verify_flow TODO_verify_il
 #define TODO_verify_stmts TODO_verify_il
···
 #define varpool_get_node(decl) varpool_node::get(decl)
 #define dump_varpool_node(file, node) (node)->dump(file)
 
-#if BUILDING_GCC_VERSION >= 8000
 #define cgraph_create_edge(caller, callee, call_stmt, count, freq) \
 	(caller)->create_edge((callee), (call_stmt), (count))
 
···
 		old_call_stmt, call_stmt, count, freq, reason)	\
 	(caller)->create_edge_including_clones((callee),	\
 		(old_call_stmt), (call_stmt), (count), (reason))
-#else
-#define cgraph_create_edge(caller, callee, call_stmt, count, freq) \
-	(caller)->create_edge((callee), (call_stmt), (count), (freq))
-
-#define cgraph_create_edge_including_clones(caller, callee,	\
-		old_call_stmt, call_stmt, count, freq, reason)	\
-	(caller)->create_edge_including_clones((callee),	\
-		(old_call_stmt), (call_stmt), (count), (freq), (reason))
-#endif
 
 typedef struct cgraph_node *cgraph_node_ptr;
 typedef struct cgraph_edge *cgraph_edge_p;
···
 	symtab->call_edge_duplication_hooks(cs1, cs2);
 }
 
-#if BUILDING_GCC_VERSION >= 6000
 typedef gimple *gimple_ptr;
 typedef const gimple *const_gimple_ptr;
 #define gimple gimple_ptr
 #define const_gimple const_gimple_ptr
 #undef CONST_CAST_GIMPLE
 #define CONST_CAST_GIMPLE(X) CONST_CAST(gimple, (X))
-#endif
 
 /* gimple related */
 static inline gimple gimple_build_assign_with_ops(enum tree_code subcode, tree lhs, tree op1, tree op2 MEM_STAT_DECL)
···
 	referring_node->remove_stmt_references(stmt);
 }
 
-#if BUILDING_GCC_VERSION < 6000
-#define get_inner_reference(exp, pbitsize, pbitpos, poffset, pmode, punsignedp, preversep, pvolatilep, keep_aligning)	\
-	get_inner_reference(exp, pbitsize, pbitpos, poffset, pmode, punsignedp, pvolatilep, keep_aligning)
-#define gen_rtx_set(ARG0, ARG1) gen_rtx_SET(VOIDmode, (ARG0), (ARG1))
-#endif
-
-#if BUILDING_GCC_VERSION >= 6000
 #define gen_rtx_set(ARG0, ARG1) gen_rtx_SET((ARG0), (ARG1))
-#endif
 
 #ifdef __cplusplus
 static inline void debug_tree(const_tree t)
···
 #define debug_gimple_stmt(s) debug_gimple_stmt(CONST_CAST_GIMPLE(s))
 #endif
 
-#if BUILDING_GCC_VERSION >= 7000
 #define get_inner_reference(exp, pbitsize, pbitpos, poffset, pmode, punsignedp, preversep, pvolatilep, keep_aligning)	\
 	get_inner_reference(exp, pbitsize, pbitpos, poffset, pmode, punsignedp, preversep, pvolatilep)
-#endif
-
-#if BUILDING_GCC_VERSION < 7000
-#define SET_DECL_ALIGN(decl, align)	DECL_ALIGN(decl) = (align)
-#define SET_DECL_MODE(decl, mode)	DECL_MODE(decl) = (mode)
-#endif
 
 #if BUILDING_GCC_VERSION >= 14000
 #define last_stmt(x)			last_nondebug_stmt(x)

scripts/min-tool-version.sh

···
 
 case "$1" in
 binutils)
-	echo 2.25.0
+	echo 2.30.0
 	;;
 gcc)
 	if [ "$ARCH" = parisc64 ]; then
 		echo 12.0.0
-	elif [ "$SRCARCH" = x86 ]; then
-		echo 8.1.0
 	else
-		echo 5.1.0
+		echo 8.1.0
 	fi
 	;;
 llvm)