[PATCH 02/18] -Wwrite-strings: Constify macroexp.c:init_shared_buffer

Pedro Alves
2017-04-04T17:25:59Z

There's one call in the file that passes a string literal, like:

init_shared_buffer (&va_arg_name, "__VA_ARGS__",
strlen ("__VA_ARGS__"));

Instead of adding a cast here, make init_shared_buffer take a 'const
char *', and remove the several casts in the file that are made
obsolete.

gdb/ChangeLog:
yyyy-mm-dd Pedro Alves <palves@redhat.com>

* macroexp.c (macro_buffer::shared): Now a bool.
(init_buffer): Update.
(init_shared_buffer): Constify 'addr' parameter.
(substitute_args, expand, macro_expand, macro_expand_next): Remove
casts.
---
gdb/macroexp.c | 26 +++++++++++++++-----------
1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/gdb/macroexp.c b/gdb/macroexp.c
index 3cc2d0b..5537d9d 100644
--- a/gdb/macroexp.c
+++ b/gdb/macroexp.c
@@ -53,8 +53,9 @@ struct macro_buffer

/* Zero if TEXT can be safely realloc'ed (i.e., it's its own malloc
block). Non-zero if TEXT is actually pointing into the middle of
- some other block, and we shouldn't reallocate it. */
- int shared;
+ some other block, or to a string literal, and we shouldn't
+ reallocate it. */
+ bool shared;

/* For detecting token splicing.

@@ -85,19 +86,22 @@ init_buffer (struct macro_buffer *b, int n)
else
b->text = NULL;
b->len = 0;
- b->shared = 0;
+ b->shared = false;
b->last_token = -1;
}

/* Set the macro buffer *BUF to refer to the LEN bytes at ADDR, as a
shared substring. */
+
static void
-init_shared_buffer (struct macro_buffer *buf, char *addr, int len)
+init_shared_buffer (struct macro_buffer *buf, const char *addr, int len)
{
- buf->text = addr;
+ /* The function accept a "const char *" addr so that clients can
+ pass in string literals without casts. */
+ buf->text = (char *) addr;
buf->len = len;
- buf->shared = 1;
+ buf->shared = true;
buf->size = 0;
buf->last_token = -1;
}
@@ -980,7 +984,7 @@ substitute_args (struct macro_buffer *dest,
lexed. */
char *lookahead_rl_start;

- init_shared_buffer (&replacement_list, (char *) def->replacement,
+ init_shared_buffer (&replacement_list, def->replacement,
strlen (def->replacement));

gdb_assert (dest->len == 0);
@@ -1199,7 +1203,7 @@ expand (const char *id,
{
struct macro_buffer replacement_list;

- init_shared_buffer (&replacement_list, (char *) def->replacement,
+ init_shared_buffer (&replacement_list, def->replacement,
strlen (def->replacement));

scan (dest, &replacement_list, &new_no_loop, lookup_func, lookup_baton);
@@ -1236,7 +1240,7 @@ expand (const char *id,
substitution parameter is the name of the formal
argument without the "...". */
init_shared_buffer (&va_arg_name,
- (char *) def->argv[def->argc - 1],
+ def->argv[def->argc - 1],
len - 3);
is_varargs = 1;
}
@@ -1415,7 +1419,7 @@ macro_expand (const char *source,
struct macro_buffer src, dest;
struct cleanup *back_to;

- init_shared_buffer (&src, (char *) source, strlen (source));
+ init_shared_buffer (&src, source, strlen (source));

init_buffer (&dest, 0);
dest.last_token = 0;
@@ -1448,7 +1452,7 @@ macro_expand_next (const char **lexptr,
struct cleanup *back_to;

/* Set up SRC to refer to the input text, pointed to by *lexptr. */
- init_shared_buffer (&src, (char *) *lexptr, strlen (*lexptr));
+ init_shared_buffer (&src, *lexptr, strlen (*lexptr));

/* Set up DEST to receive the expansion, if there is one. */
init_buffer (&dest, 0);
--
2.5.5