I got the following compile error with gcc 4.1.1 when trying to compile
kernel 2.6.18-rc4-mm2 for m68k:
<-- snip -->
...
LD .tmp_vmlinux1
arch/m68k/amiga/built-in.o: In function `amiga_get_hardware_list':
config.c:(.text+0x882): undefined reference to `strcpy'
kernel/built-in.o: In function `prof_cpu_mask_read_proc':
profile.c:(.text+0x41ac): undefined reference to `strcpy'
kernel/built-in.o: In function `sysfs_show_available_clocksources':
clocksource.c:(.text+0x1434e): undefined reference to `strcpy'
kernel/built-in.o: In function `sysfs_show_current_clocksources':
clocksource.c:(.text+0x143a4): undefined reference to `strcpy'
fs/built-in.o: In function `lock_get_status':
locks.c:(.text+0x1198a): undefined reference to `strcpy'
fs/built-in.o:locks.c:(.text+0x119ae): more undefined references to `strcpy' follow
make[1]: *** [.tmp_vmlinux1] Error 1
<-- snip -->
The Linux kernel is a freestanding environment, not a hosted one
providing a full standard C library gcc can consider being present.
The fact that -ffreestanding had already been re-added on three
architectures also reflects this fact.
If we want to use all or a subset of the gcc builtins on some or all
architectures, we should make this explicitely through #define's.
The justification of commit 6edfba1b33c701108717f4e036320fc39abe1912
"it was only added for x86-64, so dropping it should be safe" has been
proved as wrong since it broke at least mips and m68k.
This patch therefore reverts commit
6edfba1b33c701108717f4e036320fc39abe1912 and re-adds -ffreestanding to
the CFLAGS.
Signed-off-by: Adrian Bunk <[email protected]>
---
This patch was (except for a rediff due to unrelated changes) already
sent on:
- 21 Aug 2006
Makefile | 2 +-
arch/i386/Makefile | 3 ---
arch/mips/Makefile | 2 --
arch/um/Makefile-i386 | 4 ----
include/asm-x86_64/string.h | 18 ++++++++++++++----
5 files changed, 15 insertions(+), 14 deletions(-)
--- linux-2.6.18-rc4-mm2/arch/i386/Makefile.old 2006-08-21 20:40:26.000000000 +0200
+++ linux-2.6.18-rc4-mm2/arch/i386/Makefile 2006-08-21 20:40:33.000000000 +0200
@@ -39,9 +39,6 @@
cflags-$(CONFIG_REGPARM) += -mregparm=3
-# temporary until string.h is fixed
-cflags-y += -ffreestanding
-
# Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use
# a lot more stack due to the lack of sharing of stacklots:
CFLAGS += $(shell if [ $(call cc-version) -lt 0400 ] ; then echo $(call cc-option,-fno-unit-at-a-time); fi ;)
--- linux-2.6.18-rc4-mm2/arch/mips/Makefile.old 2006-08-21 20:40:40.000000000 +0200
+++ linux-2.6.18-rc4-mm2/arch/mips/Makefile 2006-08-21 20:40:48.000000000 +0200
@@ -83,8 +83,6 @@
LDFLAGS_vmlinux += -G 0 -static -n -nostdlib
MODFLAGS += -mlong-calls
-cflags-y += -ffreestanding
-
#
# We explicitly add the endianness specifier if needed, this allows
# to compile kernels with a toolchain for the other endianness. We
--- linux-2.6.18-rc4-mm2/arch/um/Makefile-i386.old 2006-08-21 20:40:56.000000000 +0200
+++ linux-2.6.18-rc4-mm2/arch/um/Makefile-i386 2006-08-21 20:41:09.000000000 +0200
@@ -33,9 +33,5 @@
# prevent gcc from keeping the stack 16 byte aligned. Taken from i386.
cflags-y += $(call cc-option,-mpreferred-stack-boundary=2)
-# Prevent sprintf in nfsd from being converted to strcpy and resulting in
-# an unresolved reference.
-cflags-y += -ffreestanding
-
CFLAGS += $(cflags-y)
USER_CFLAGS += $(cflags-y)
--- linux-2.6.18-rc4-mm2/include/asm-x86_64/string.h.old 2006-08-21 20:49:07.000000000 +0200
+++ linux-2.6.18-rc4-mm2/include/asm-x86_64/string.h 2006-08-21 20:49:22.000000000 +0200
@@ -41,15 +41,26 @@
#define __HAVE_ARCH_MEMSET
-void *memset(void *s, int c, size_t n);
+#define memset __builtin_memset
#define __HAVE_ARCH_MEMMOVE
void * memmove(void * dest,const void *src,size_t count);
+/* Use C out of line version for memcmp */
+#define memcmp __builtin_memcmp
int memcmp(const void * cs,const void * ct,size_t count);
+
+/* out of line string functions use always C versions */
+#define strlen __builtin_strlen
size_t strlen(const char * s);
-char *strcpy(char * dest,const char *src);
-char *strcat(char * dest, const char * src);
+
+#define strcpy __builtin_strcpy
+char * strcpy(char * dest,const char *src);
+
+#define strcat __builtin_strcat
+char * strcat(char * dest, const char * src);
+
+#define strcmp __builtin_strcmp
int strcmp(const char * cs,const char * ct);
#endif /* __KERNEL__ */
--- linux-2.6.18-rc4-mm3/Makefile.old 2006-08-30 16:59:31.000000000 +0200
+++ linux-2.6.18-rc4-mm3/Makefile 2006-08-30 17:02:42.000000000 +0200
@@ -308,7 +308,7 @@
CPPFLAGS := -D__KERNEL__ $(LINUXINCLUDE)
CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
- -fno-strict-aliasing -fno-common
+ -fno-strict-aliasing -fno-common -ffreestanding
AFLAGS := -D__ASSEMBLY__
# Read KERNELRELEASE from include/config/kernel.release (if it exists)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
