[PATCH 10/36] Add extern "C" to declarations of C symbols

Pedro Alves
2015-02-09T23:54:24Z

These symbols are defined in C code, so in C++ mode we need to use
extern "C" to declare them. As extern "C" can't be used inside a
function's scope, we move the declarations to the global scope at the
same time.

As for the linux-tdep.c change: elf-bfd.h wraps itself in extern "C"
already, while elf/common.h does not. Since elf/common.h is already
included by "elf-bfd.h", simply remove the explicit elf/common.h
include.

gdb/ChangeLog:
2015-02-09 Pedro Alves <palves@redhat.com>

* cli-out.c (_rl_erase_entire_line): Move declaration out of
cli_mld_erase_entire_line, and make it extern "C".
* common/common-defs.h (EXTERN_C): New.
* completer.c (_rl_completion_prefix_display_length)
(_rl_print_completions_horizontally, QSFUNC): Move declarations
out of gdb_display_match_list_1.
(_rl_qsort_string_compare): Move declaration out of
gdb_display_match_list_1, and make it extern "C".
* defs.h (re_comp): Use EXTERN_C.
* linux-tdep.c: Don't include elf/common.h.
* maint.c (_mcleanup): Move declaration out of mcleanup_wrapper,
and make it extern "C".
(monstartup): Move declaration out of maintenance_set_profile_cmd,
and make it extern "C".
(main): Move declaration out of maintenance_set_profile_cmd.
* nat/linux-ptrace.c (linux_ptrace_attach_fail_reason_string): Use
EXTERN_C.
---
gdb/cli-out.c | 4 ++--
gdb/common/common-defs.h | 6 ++++++
gdb/completer.c | 10 ++++++----
gdb/defs.h | 2 +-
gdb/linux-tdep.c | 1 -
gdb/maint.c | 10 +++++-----
gdb/nat/linux-ptrace.c | 2 +-
7 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/gdb/cli-out.c b/gdb/cli-out.c
index 48f2a04..2a83169 100644
--- a/gdb/cli-out.c
+++ b/gdb/cli-out.c
@@ -452,13 +452,13 @@ cli_mld_flush (const struct match_list_displayer *displayer)
fflush (rl_outstream);
}

+EXTERN_C void _rl_erase_entire_line (void);
+
/* CLI version of displayer.erase_entire_line. */

static void
cli_mld_erase_entire_line (const struct match_list_displayer *displayer)
{
- extern void _rl_erase_entire_line (void);
-
_rl_erase_entire_line ();
}

diff --git a/gdb/common/common-defs.h b/gdb/common/common-defs.h
index e80d332..3020bd8 100644
--- a/gdb/common/common-defs.h
+++ b/gdb/common/common-defs.h
@@ -50,4 +50,10 @@
#include "cleanups.h"
#include "common-exceptions.h"

+#ifdef __cplusplus
+# define EXTERN_C extern "C"
+#else
+# define EXTERN_C extern
+#endif
+
#endif /* COMMON_DEFS_H */
diff --git a/gdb/completer.c b/gdb/completer.c
index bfd2788..774fb31 100644
--- a/gdb/completer.c
+++ b/gdb/completer.c
@@ -1555,6 +1555,12 @@ gdb_complete_get_screenwidth (const struct match_list_displayer *displayer)
return displayer->width;
}

+extern int _rl_completion_prefix_display_length;
+extern int _rl_print_completions_horizontally;
+
+EXTERN_C int _rl_qsort_string_compare (const void *, const void *);
+typedef int QSFUNC (const void *, const void *);
+
/* GDB version of readline/complete.c:rl_display_match_list.
See gdb_display_match_list for a description of MATCHES, LEN, MAX.
Returns non-zero if all matches are displayed. */
@@ -1567,10 +1573,6 @@ gdb_display_match_list_1 (char **matches, int len, int max,
int i, j, k, l, common_length, sind;
char *temp, *t;
int page_completions = displayer->height != INT_MAX && pagination_enabled;
- extern int _rl_completion_prefix_display_length;
- extern int _rl_qsort_string_compare (const void *, const void *);
- extern int _rl_print_completions_horizontally;
- typedef int QSFUNC (const void *, const void *);

/* Find the length of the prefix common to all items: length as displayed
characters (common_length) and as a byte index into the matches (sind) */
diff --git a/gdb/defs.h b/gdb/defs.h
index a1cd45f..72512f6 100644
--- a/gdb/defs.h
+++ b/gdb/defs.h
@@ -249,7 +249,7 @@ extern int annotation_level; /* in stack.c */
"const char *" in unistd.h, so we can't declare the argument
as "char *". */

-extern char *re_comp (const char *);
+EXTERN_C char *re_comp (const char *);

/* From symfile.c */

diff --git a/gdb/linux-tdep.c b/gdb/linux-tdep.c
index d9884f3..64684d0 100644
--- a/gdb/linux-tdep.c
+++ b/gdb/linux-tdep.c
@@ -26,7 +26,6 @@
#include "gdbcore.h"
#include "regcache.h"
#include "regset.h"
-#include "elf/common.h"
#include "elf-bfd.h" /* for elfcore_write_* */
#include "inferior.h"
#include "cli/cli-utils.h"
diff --git a/gdb/maint.c b/gdb/maint.c
index be18a32..1adea2f 100644
--- a/gdb/maint.c
+++ b/gdb/maint.c
@@ -683,15 +683,18 @@ extern char etext;

static int profiling_state;

+EXTERN_C void _mcleanup (void);
+
static void
mcleanup_wrapper (void)
{
- extern void _mcleanup (void);
-
if (profiling_state)
_mcleanup ();
}

+EXTERN_C void monstartup (unsigned long, unsigned long);
+extern int main ();
+
static void
maintenance_set_profile_cmd (char *args, int from_tty,
struct cmd_list_element *c)
@@ -705,9 +708,6 @@ maintenance_set_profile_cmd (char *args, int from_tty,
{
static int profiling_initialized;

- extern void monstartup (unsigned long, unsigned long);
- extern int main();
-
if (!profiling_initialized)
{
atexit (mcleanup_wrapper);
diff --git a/gdb/nat/linux-ptrace.c b/gdb/nat/linux-ptrace.c
index 0ce258f..e36864c 100644
--- a/gdb/nat/linux-ptrace.c
+++ b/gdb/nat/linux-ptrace.c
@@ -84,7 +84,7 @@ linux_ptrace_attach_fail_reason_string (ptid_t ptid, int err)
#if defined __i386__ || defined __x86_64__

/* Address of the 'ret' instruction in asm code block below. */
-extern void (linux_ptrace_test_ret_to_nx_instr) (void);
+EXTERN_C void linux_ptrace_test_ret_to_nx_instr (void);

#include <sys/reg.h>
#include <sys/mman.h>
--
1.9.3