[PATCH v2 06/10] riscv: fix duplicate extern declarations

[Safocl Stollmannovic]

Compiling a kernel module with a C++ compiler results in a "duplicate
extern specifier" error.
This occurs because the code contains `extern asmlinkage`, and `asmlinkage`
expands to `extern C` when processed by a C++ compiler.
Since the code already contains sections that respond to a C++ compiler,
I believe it is a perfectly valid approach to gradually move toward a state
where kernel modules can be compiled by a C++ compiler without any issues.
The `extern` specifier must be removed.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=222257

Signed-off-by: Safocl Stollmannovic <safocl88 at gmail.com>
---
 arch/riscv/include/asm/string.h | 24 ++++++++++++------------
 arch/riscv/kernel/process.c     |  4 ++--
 arch/riscv/kernel/stacktrace.c  |  2 +-
 3 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/arch/riscv/include/asm/string.h b/arch/riscv/include/asm/string.h
index 764ffe8f6..ac895358c 100644
--- a/arch/riscv/include/asm/string.h
+++ b/arch/riscv/include/asm/string.h
@@ -10,33 +10,33 @@
 #include <linux/linkage.h>
 
 #define __HAVE_ARCH_MEMSET
-extern asmlinkage void *memset(void *, int, size_t);
-extern asmlinkage void *__memset(void *, int, size_t);
+asmlinkage void *memset(void *, int, size_t);
+asmlinkage void *__memset(void *, int, size_t);
 #define __HAVE_ARCH_MEMCPY
-extern asmlinkage void *memcpy(void *, const void *, size_t);
-extern asmlinkage void *__memcpy(void *, const void *, size_t);
+asmlinkage void *memcpy(void *, const void *, size_t);
+asmlinkage void *__memcpy(void *, const void *, size_t);
 #define __HAVE_ARCH_MEMMOVE
-extern asmlinkage void *memmove(void *, const void *, size_t);
-extern asmlinkage void *__memmove(void *, const void *, size_t);
+asmlinkage void *memmove(void *, const void *, size_t);
+asmlinkage void *__memmove(void *, const void *, size_t);
 
 #if !(defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS))
 #define __HAVE_ARCH_STRCMP
-extern asmlinkage int strcmp(const char *cs, const char *ct);
+asmlinkage int strcmp(const char *cs, const char *ct);
 
 #define __HAVE_ARCH_STRLEN
-extern asmlinkage __kernel_size_t strlen(const char *);
+asmlinkage __kernel_size_t strlen(const char *);
 
 #define __HAVE_ARCH_STRNCMP
-extern asmlinkage int strncmp(const char *cs, const char *ct, size_t count);
+asmlinkage int strncmp(const char *cs, const char *ct, size_t count);
 
 #define __HAVE_ARCH_STRNLEN
-extern asmlinkage __kernel_size_t strnlen(const char *, size_t);
+asmlinkage __kernel_size_t strnlen(const char *, size_t);
 
 #define __HAVE_ARCH_STRCHR
-extern asmlinkage char *strchr(const char *, int);
+asmlinkage char *strchr(const char *, int);
 
 #define __HAVE_ARCH_STRRCHR
-extern asmlinkage char *strrchr(const char *, int);
+asmlinkage char *strrchr(const char *, int);
 #endif
 
 /* For those files which don't want to check by kasan. */
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index 34c1d498d..3e531b6d0 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -39,8 +39,8 @@ unsigned long __stack_chk_guard __read_mostly;
 EXPORT_SYMBOL(__stack_chk_guard);
 #endif
 
-extern asmlinkage void ret_from_fork_kernel_asm(void);
-extern asmlinkage void ret_from_fork_user_asm(void);
+asmlinkage void ret_from_fork_kernel_asm(void);
+asmlinkage void ret_from_fork_user_asm(void);
 
 void noinstr arch_cpu_idle(void)
 {
diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c
index c75554471..6ca60cd3d 100644
--- a/arch/riscv/kernel/stacktrace.c
+++ b/arch/riscv/kernel/stacktrace.c
@@ -32,7 +32,7 @@
 	val;						\
 })
 
-extern asmlinkage void handle_exception(void);
+asmlinkage void handle_exception(void);
 extern unsigned long ret_from_exception_end;
 
 static inline int fp_is_valid(unsigned long fp, unsigned long sp)
-- 
2.56.1