[PATCH] remove gcc-2 checks

Remove various things which were checking for gcc-1.x and gcc-2.x compilers.

From: Adrian Bunk <[e-mail]>

Some documentation updates and removes some code paths for gcc < 3.2.

Acked-by: Russell King <[e-mail]>
Signed-off-by: Adrian Bunk <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

Documentation/Changes

···
 Eine deutsche Version dieser Datei finden Sie unter
 <http://www.stefan-winter.de/Changes-2.4.0.txt>.
 
-Last updated: October 29th, 2002
-
 Chris Ricker ([e-mail] or [e-mail]).
 
 Current Minimal Requirements
···
 hardware, for example, you probably needn't concern yourself with
 isdn4k-utils.
 
-o  Gnu C                  2.95.3                  # gcc --version
+o  Gnu C                  3.2                     # gcc --version
 o  Gnu make               3.79.1                  # make --version
 o  binutils               2.12                    # ld -v
 o  util-linux             2.10o                   # fdformat --version
···
 ---
 
 The gcc version requirements may vary depending on the type of CPU in your
-computer. The next paragraph applies to users of x86 CPUs, but not
-necessarily to users of other CPUs. Users of other CPUs should obtain
-information about their gcc version requirements from another source.
-
-The recommended compiler for the kernel is gcc 2.95.x (x >= 3), and it
-should be used when you need absolute stability. You may use gcc 3.0.x
-instead if you wish, although it may cause problems. Later versions of gcc 
-have not received much testing for Linux kernel compilation, and there are 
-almost certainly bugs (mainly, but not exclusively, in the kernel) that
-will need to be fixed in order to use these compilers. In any case, using
-pgcc instead of plain gcc is just asking for trouble.
-
-The Red Hat gcc 2.96 compiler subtree can also be used to build this tree.
-You should ensure you use gcc-2.96-74 or later. gcc-2.96-54 will not build
-the kernel correctly.
-
-In addition, please pay attention to compiler optimization.  Anything
-greater than -O2 may not be wise.  Similarly, if you choose to use gcc-2.95.x
-or derivatives, be sure not to use -fstrict-aliasing (which, depending on
-your version of gcc 2.95.x, may necessitate using -fno-strict-aliasing).
+computer.
 
 Make
 ----
···
 Kernel compilation
 ******************
 
-gcc 2.95.3
-----------
-o  <ftp://ftp.gnu.org/gnu/gcc/gcc-2.95.3.tar.gz>
+gcc
+---
+o  <ftp://ftp.gnu.org/gnu/gcc/>
 
 Make
 ----

README

···
 
 COMPILING the kernel:
 
- - Make sure you have gcc 2.95.3 available.
-   gcc 2.91.66 (egcs-1.1.2), and gcc 2.7.2.3 are known to miscompile
-   some parts of the kernel, and are *no longer supported*.
-   Also remember to upgrade your binutils package (for as/ld/nm and company)
-   if necessary. For more information, refer to Documentation/Changes.
+ - Make sure you have at least gcc 3.2 available.
+   For more information, refer to Documentation/Changes.
 
    Please note that you can still run a.out user programs with this kernel.
 

arch/arm/kernel/asm-offsets.c

···
 #error Sorry, your compiler targets APCS-26 but this kernel requires APCS-32
 #endif
 /*
- * GCC 2.95.1, 2.95.2: ignores register clobber list in asm().
  * GCC 3.0, 3.1: general bad code generation.
  * GCC 3.2.0: incorrect function argument offset calculation.
  * GCC 3.2.x: miscompiles NEW_AUX_ENT in fs/binfmt_elf.c
  *            (http://gcc.gnu.org/PR8896) and incorrect structure
  *	      initialisation in fs/jffs2/erase.c
  */
-#if __GNUC__ < 2 || \
-   (__GNUC__ == 2 && __GNUC_MINOR__ < 95) || \
-   (__GNUC__ == 2 && __GNUC_MINOR__ == 95 && __GNUC_PATCHLEVEL__ != 0 && \
-					     __GNUC_PATCHLEVEL__ < 3) || \
-   (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
+#if (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
 #error Your compiler is too buggy; it is known to miscompile kernels.
-#error    Known good compilers: 2.95.3, 2.95.4, 2.96, 3.3
+#error    Known good compilers: 3.3
 #endif
 
 /* Use marker if you need to separate the values later */

arch/arm26/kernel/asm-offsets.c

···
 #if defined(__APCS_32__) && defined(CONFIG_CPU_26)
 #error Sorry, your compiler targets APCS-32 but this kernel requires APCS-26
 #endif
-#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 95)
-#error Sorry, your compiler is known to miscompile kernels.  Only use gcc 2.95.3 and later.
-#endif
-#if __GNUC__ == 2 && __GNUC_MINOR__ == 95
-/* shame we can't detect the .1 or .2 releases */
-#warning GCC 2.95.2 and earlier miscompiles kernels.
-#endif
 
 /* Use marker if you need to separate the values later */
 

arch/i386/Kconfig

···
 	and passes the first three arguments of a function call in registers.
 	This will probably break binary only modules.
 
-	This feature is only enabled for gcc-3.0 and later - earlier compilers
-	generate incorrect output with certain kernel constructs when
-	-mregparm=3 is used.
-
 config SECCOMP
 	bool "Enable seccomp to safely compute untrusted bytecode"
 	depends on PROC_FS

arch/i386/Makefile

···
 # CPU-specific tuning. Anything which can be shared with UML should go here.
 include $(srctree)/arch/i386/Makefile.cpu
 
-# -mregparm=3 works ok on gcc-3.0 and later
-#
-GCC_VERSION			:= $(call cc-version)
-cflags-$(CONFIG_REGPARM) 	+= $(shell if [ $(GCC_VERSION) -ge 0300 ] ; then echo "-mregparm=3"; fi ;)
+cflags-$(CONFIG_REGPARM) 	+= -mregparm=3
 
 # Disable unit-at-a-time mode, it makes gcc use a lot more stack
 # due to the lack of sharing of stacklots.

arch/i386/Makefile.cpu

···
 # CPU tuning section - shared with UML.
 # Must change only cflags-y (or [yn]), not CFLAGS! That makes a difference for UML.
 
-#-mtune exists since gcc 3.4, and some -mcpu flavors didn't exist in gcc 2.95.
+#-mtune exists since gcc 3.4
 HAS_MTUNE	:= $(call cc-option-yn, -mtune=i386)
 ifeq ($(HAS_MTUNE),y)
 tune		= $(call cc-option,-mtune=$(1),)
···
 cflags-$(CONFIG_M486)		+= -march=i486
 cflags-$(CONFIG_M586)		+= -march=i586
 cflags-$(CONFIG_M586TSC)	+= -march=i586
-cflags-$(CONFIG_M586MMX)	+= $(call cc-option,-march=pentium-mmx,-march=i586)
+cflags-$(CONFIG_M586MMX)	+= -march=pentium-mmx
 cflags-$(CONFIG_M686)		+= -march=i686
 cflags-$(CONFIG_MPENTIUMII)	+= -march=i686 $(call tune,pentium2)
 cflags-$(CONFIG_MPENTIUMIII)	+= -march=i686 $(call tune,pentium3)
···
 cflags-$(CONFIG_MK6)		+= -march=k6
 # Please note, that patches that add -march=athlon-xp and friends are pointless.
 # They make zero difference whatsosever to performance at this time.
-cflags-$(CONFIG_MK7)		+= $(call cc-option,-march=athlon,-march=i686 $(align)-functions=4)
-cflags-$(CONFIG_MK8)		+= $(call cc-option,-march=k8,$(call cc-option,-march=athlon,-march=i686 $(align)-functions=4))
+cflags-$(CONFIG_MK7)		+= -march=athlon
+cflags-$(CONFIG_MK8)		+= $(call cc-option,-march=k8,-march=athlon)
 cflags-$(CONFIG_MCRUSOE)	+= -march=i686 $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
 cflags-$(CONFIG_MEFFICEON)	+= -march=i686 $(call tune,pentium3) $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
 cflags-$(CONFIG_MWINCHIPC6)	+= $(call cc-option,-march=winchip-c6,-march=i586)
···
 cflags-$(CONFIG_X86_ELAN)	+= -march=i486
 
 # Geode GX1 support
-cflags-$(CONFIG_MGEODEGX1)		+= $(call cc-option,-march=pentium-mmx,-march=i486)
+cflags-$(CONFIG_MGEODEGX1)	+= -march=pentium-mmx
 

arch/ia64/Makefile

···
 		ftp://ftp.hpl.hp.com/pub/linux-ia64/gas-030124.tar.gz)
 endif
 
-ifneq ($(shell if [ $(GCC_VERSION) -lt 0300 ] ; then echo "bad"; fi ;),)
-$(error Sorry, your compiler is too old.  GCC v2.96 is known to generate bad code.)
-endif
-
 ifeq ($(GCC_VERSION),0304)
 	cflags-$(CONFIG_ITANIUM)	+= -mtune=merced
 	cflags-$(CONFIG_MCKINLEY)	+= -mtune=mckinley

arch/ia64/kernel/head.S

···
 	 * the clobber lists for spin_lock() in include/asm-ia64/spinlock.h.
 	 */
 
-#if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
+#if (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
 
 GLOBAL_ENTRY(ia64_spinlock_contention_pre3_4)
 	.prologue

arch/ia64/kernel/ia64_ksyms.c

···
 
 #ifdef ASM_SUPPORTED
 # ifdef CONFIG_SMP
-#  if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
+#  if (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
 /*
  * This is not a normal routine and we don't want a function descriptor for it, so we use
  * a fake declaration here.

arch/ia64/oprofile/backtrace.c

···
 	u64 *prev_pfs_loc;	/* state for WAR for old spinlock ool code */
 } ia64_backtrace_t;
 
-#if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
+#if (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
 /*
  * Returns non-zero if the PC is in the spinlock contention out-of-line code
  * with non-standard calling sequence (on older compilers).

drivers/md/raid0.c

···
 	printk("raid0 : conf->hash_spacing is %llu blocks.\n",
 		(unsigned long long)conf->hash_spacing);
 	{
-#if __GNUC__ < 3
-		volatile
-#endif
 		sector_t s = mddev->array_size;
 		sector_t space = conf->hash_spacing;
 		int round;
···
  
 
 	{
-#if __GNUC__ < 3
-		volatile
-#endif
 		sector_t x = block >> conf->preshift;
 		sector_div(x, (u32)conf->hash_spacing);
 		zone = conf->hash_table[x];

drivers/media/video/v4l2-common.c

···
 };
 
 char *v4l2_ioctl_names[256] = {
-#if __GNUC__ >= 3
 	[0 ... 255]                      = "UNKNOWN",
-#endif
 	[_IOC_NR(VIDIOC_QUERYCAP)]       = "VIDIOC_QUERYCAP",
 	[_IOC_NR(VIDIOC_RESERVED)]       = "VIDIOC_RESERVED",
 	[_IOC_NR(VIDIOC_ENUM_FMT)]       = "VIDIOC_ENUM_FMT",

fs/ocfs2/cluster/masklog.h

···
 	mlog(ML_ENTRY, "ENTRY:\n");					\
 } while (0)
 
-/* We disable this for old compilers since they don't have support for
- * __builtin_types_compatible_p.
+/*
+ * We disable this for sparse.
  */
-#if (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1)) && \
-    !defined(__CHECKER__)
+#if !defined(__CHECKER__)
 #define mlog_exit(st) do {						     \
 	if (__builtin_types_compatible_p(typeof(st), unsigned long))	     \
 		mlog(ML_EXIT, "EXIT: %lu\n", (unsigned long) (st));	     \

fs/xfs/xfs_log.h

···
  * By comparing each compnent, we don't have to worry about extra
  * endian issues in treating two 32 bit numbers as one 64 bit number
  */
-static
-#if defined(__GNUC__) && (__GNUC__ == 2) && ( (__GNUC_MINOR__ == 95) || (__GNUC_MINOR__ == 96))
-__attribute__((unused))	/* gcc 2.95, 2.96 miscompile this when inlined */
-#else
-__inline__
-#endif
-xfs_lsn_t	_lsn_cmp(xfs_lsn_t lsn1, xfs_lsn_t lsn2)
+static inline xfs_lsn_t	_lsn_cmp(xfs_lsn_t lsn1, xfs_lsn_t lsn2)
 {
 	if (CYCLE_LSN(lsn1) != CYCLE_LSN(lsn2))
 		return (CYCLE_LSN(lsn1)<CYCLE_LSN(lsn2))? -999 : 999;

include/asm-alpha/compiler.h

···
 #undef inline
 #undef __inline__
 #undef __inline
-#if __GNUC__ == 3 && __GNUC_MINOR__ >= 1 || __GNUC__ > 3
 #undef __always_inline
 #define __always_inline		inline __attribute__((always_inline))
-#endif
 
 #endif /* __ALPHA_COMPILER_H */

include/asm-alpha/processor.h

···
 #define spin_lock_prefetch(lock)  	do { } while (0)
 #endif
 
-#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1)
 extern inline void prefetch(const void *ptr)  
 { 
 	__builtin_prefetch(ptr, 0, 3);
···
 	__builtin_prefetch(ptr, 1, 3);
 }
 #endif
-
-#else
-extern inline void prefetch(const void *ptr)  
-{ 
-	__asm__ ("ldl $31,%0" : : "m"(*(char *)ptr)); 
-}
-
-extern inline void prefetchw(const void *ptr)  
-{
-	__asm__ ("ldq $31,%0" : : "m"(*(char *)ptr)); 
-}
-
-#ifdef CONFIG_SMP
-extern inline void spin_lock_prefetch(const void *ptr)  
-{
-	__asm__ ("ldq $31,%0" : : "m"(*(char *)ptr)); 
-}
-#endif
-
-#endif /* GCC 3.1 */
 
 #endif /* __ASM_ALPHA_PROCESSOR_H */

include/asm-ia64/bug.h

···
 #define _ASM_IA64_BUG_H
 
 #ifdef CONFIG_BUG
-#if (__GNUC__ > 3) || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1)
-# define ia64_abort()	__builtin_trap()
-#else
-# define ia64_abort()	(*(volatile int *) 0 = 0)
-#endif
+#define ia64_abort()	__builtin_trap()
 #define BUG() do { printk("kernel BUG at %s:%d!\n", __FILE__, __LINE__); ia64_abort(); } while (0)
 
 /* should this BUG be made generic? */

include/asm-ia64/spinlock.h

···
 {
 	register volatile unsigned int *ptr asm ("r31") = &lock->lock;
 
-#if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
+#if (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
 # ifdef CONFIG_ITANIUM
 	/* don't use brl on Itanium... */
 	asm volatile ("{\n\t"

include/asm-sparc64/system.h

···
 	 * not preserve it's value.  Hairy, but it lets us remove 2 loads
 	 * and 2 stores in this critical code path.  -DaveM
 	 */
-#if __GNUC__ >= 3
 #define EXTRA_CLOBBER ,"%l1"
-#else
-#define EXTRA_CLOBBER
-#endif
 #define switch_to(prev, next, last)					\
 do {	if (test_thread_flag(TIF_PERFCTR)) {				\
 		unsigned long __tmp;					\

include/asm-um/rwsem.h

···
 #ifndef __UM_RWSEM_H__
 #define __UM_RWSEM_H__
 
-#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 96)
-#define __builtin_expect(exp,c) (exp)
-#endif
-
 #include "asm/arch/rwsem.h"
 
 #endif

include/asm-v850/unistd.h

···
 /* User programs sometimes end up including this header file
    (indirectly, via uClibc header files), so I'm a bit nervous just
    including <linux/compiler.h>.  */
-#if !defined(__builtin_expect) && __GNUC__ == 2 && __GNUC_MINOR__ < 96
-#define __builtin_expect(x, expected_value) (x)
-#endif
 
 #define __syscall_return(type, res)					      \
   do {									      \
···
   __syscall_return (type, __ret);					      \
 }
 
-#if __GNUC__ < 3
-/* In older versions of gcc, `asm' statements with more than 10
-   input/output arguments produce a fatal error.  To work around this
-   problem, we use two versions, one for gcc-3.x and one for earlier
-   versions of gcc (the `earlier gcc' version doesn't work with gcc-3.x
-   because gcc-3.x doesn't allow clobbers to also be input arguments).  */
-#define __SYSCALL6_TRAP(syscall, ret, a, b, c, d, e, f)			      \
-  __asm__ __volatile__ ("trap " SYSCALL_LONG_TRAP			      \
-			: "=r" (ret), "=r" (syscall)			      \
-			: "1" (syscall),				      \
-			"r" (a), "r" (b), "r" (c), "r" (d),		      \
- 			"r" (e), "r" (f)				      \
-			: SYSCALL_CLOBBERS, SYSCALL_ARG4, SYSCALL_ARG5);
-#else /* __GNUC__ >= 3 */
 #define __SYSCALL6_TRAP(syscall, ret, a, b, c, d, e, f)			      \
   __asm__ __volatile__ ("trap " SYSCALL_LONG_TRAP			      \
 			: "=r" (ret), "=r" (syscall),			      \
···
 			"r" (a), "r" (b), "r" (c), "r" (d),		      \
 			"2" (e), "3" (f)				      \
 			: SYSCALL_CLOBBERS);
-#endif
 
 #define _syscall6(type, name, atype, a, btype, b, ctype, c, dtype, d, etype, e, ftype, f) \
 type name (atype a, btype b, ctype c, dtype d, etype e, ftype f)	      \

include/linux/byteorder/generic.h

···
 extern __u16			ntohs(__be16);
 extern __be16			htons(__u16);
 
-#if defined(__GNUC__) && (__GNUC__ >= 2) && defined(__OPTIMIZE__)
+#if defined(__GNUC__) && defined(__OPTIMIZE__)
 
 #define ___htonl(x) __cpu_to_be32(x)
 #define ___htons(x) __cpu_to_be16(x)

include/linux/byteorder/swab.h

···
 /*
  * Allow constant folding
  */
-#if defined(__GNUC__) && (__GNUC__ >= 2) && defined(__OPTIMIZE__)
+#if defined(__GNUC__) && defined(__OPTIMIZE__)
 #  define __swab16(x) \
 (__builtin_constant_p((__u16)(x)) ? \
  ___swab16((x)) : \

include/linux/byteorder/swabb.h

···
 /*
  * Allow constant folding
  */
-#if defined(__GNUC__) && (__GNUC__ >= 2) && defined(__OPTIMIZE__)
+#if defined(__GNUC__) && defined(__OPTIMIZE__)
 #  define __swahw32(x) \
 (__builtin_constant_p((__u32)(x)) ? \
  ___swahw32((x)) : \

include/linux/compiler-gcc.h

···
   ({ unsigned long __ptr;					\
     __asm__ ("" : "=g"(__ptr) : "0"(ptr));		\
     (typeof(ptr)) (__ptr + (off)); })
+
+
+#define inline		inline		__attribute__((always_inline))
+#define __inline__	__inline__	__attribute__((always_inline))
+#define __inline	__inline	__attribute__((always_inline))
+#define __deprecated			__attribute__((deprecated))
+#define  noinline			__attribute__((noinline))
+#define __attribute_pure__		__attribute__((pure))
+#define __attribute_const__		__attribute__((__const__))

include/linux/compiler-gcc3.h

···
 /* These definitions are for GCC v3.x.  */
 #include <linux/compiler-gcc.h>
 
-#if __GNUC_MINOR__ >= 1
-# define inline		inline		__attribute__((always_inline))
-# define __inline__	__inline__	__attribute__((always_inline))
-# define __inline	__inline	__attribute__((always_inline))
-#endif
-
-#if __GNUC_MINOR__ > 0
-# define __deprecated		__attribute__((deprecated))
-#endif
-
 #if __GNUC_MINOR__ >= 3
 # define __attribute_used__	__attribute__((__used__))
 #else
 # define __attribute_used__	__attribute__((__unused__))
-#endif
-
-#define __attribute_pure__	__attribute__((pure))
-#define __attribute_const__	__attribute__((__const__))
-
-#if __GNUC_MINOR__ >= 1
-#define  noinline		__attribute__((noinline))
 #endif
 
 #if __GNUC_MINOR__ >= 4

include/linux/compiler-gcc4.h

···
 /* These definitions are for GCC v4.x.  */
 #include <linux/compiler-gcc.h>
 
-#define inline			inline		__attribute__((always_inline))
-#define __inline__		__inline__	__attribute__((always_inline))
-#define __inline		__inline	__attribute__((always_inline))
-#define __deprecated		__attribute__((deprecated))
 #define __attribute_used__	__attribute__((__used__))
-#define __attribute_pure__	__attribute__((pure))
-#define __attribute_const__	__attribute__((__const__))
-#define  noinline		__attribute__((noinline))
 #define __must_check 		__attribute__((warn_unused_result))
 #define __compiler_offsetof(a,b) __builtin_offsetof(a,b)
 

include/linux/kernel.h

···
 #endif
 
 /* Trap pasters of __FUNCTION__ at compile-time */
-#if __GNUC__ > 2 || __GNUC_MINOR__ >= 95
 #define __FUNCTION__ (__func__)
-#endif
 
 #endif

include/linux/seccomp.h

···
 
 #else /* CONFIG_SECCOMP */
 
-#if (__GNUC__ > 2)
-  typedef struct { } seccomp_t;
-#else
-  typedef struct { int gcc_is_buggy; } seccomp_t;
-#endif
+typedef struct { } seccomp_t;
 
 #define secure_computing(x) do { } while (0)
 /* static inline to preserve typechecking */

include/linux/spinlock_types_up.h

···
 
 #else
 
-/*
- * All gcc 2.95 versions and early versions of 2.96 have a nasty bug
- * with empty initializers.
- */
-#if (__GNUC__ > 2)
 typedef struct { } raw_spinlock_t;
 
 #define __RAW_SPIN_LOCK_UNLOCKED { }
-#else
-typedef struct { int gcc_is_buggy; } raw_spinlock_t;
-#define __RAW_SPIN_LOCK_UNLOCKED (raw_spinlock_t) { 0 }
-#endif
 
 #endif
 
-#if (__GNUC__ > 2)
 typedef struct {
 	/* no debug version on UP */
 } raw_rwlock_t;
 
 #define __RAW_RW_LOCK_UNLOCKED { }
-#else
-typedef struct { int gcc_is_buggy; } raw_rwlock_t;
-#define __RAW_RW_LOCK_UNLOCKED (raw_rwlock_t) { 0 }
-#endif
 
 #endif /* __LINUX_SPINLOCK_TYPES_UP_H */

sound/isa/wavefront/wavefront_synth.c

···
 
 #ifdef WF_DEBUG
 
-#if defined(NEW_MACRO_VARARGS) || __GNUC__ >= 3
 #define DPRINT(cond, ...) \
        if ((dev->debug & (cond)) == (cond)) { \
 	     snd_printk (__VA_ARGS__); \
        }
-#else
-#define DPRINT(cond, args...) \
-       if ((dev->debug & (cond)) == (cond)) { \
-	     snd_printk (args); \
-       }
-#endif
 #else
 #define DPRINT(cond, args...)
 #endif /* WF_DEBUG */