cortex_m: fix scan-build false positive

Scan-build is unable to detect that 'target->dbg_msg_enabled' does
not change across the function cortex_m_fast_read_all_regs().
It incorrectly assumes that it can be false at the first check (so
'dcrdr' get not assigned) and it is true later on (when 'dcrdr'
get used).
This triggers a false positive:
	src/target/cortex_m.c:338:12: warning:
		3rd function call argument is an uninitialized value
		[core.CallAndMessage]
	retval = mem_ap_write_atomic_u32(armv7m->debug_ap, DCB_DCRDR, dcrdr);

Use a local variable for 'target->dbg_msg_enabled' so scan-build
can track it as not modified.
While there, change the type of 'target->dbg_msg_enabled' to
boolean as there is no reason to use uint32_t.

Change-Id: Icaf1a1b2dea8bc55108182ea440708ab76396cd7
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/8391
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
This commit is contained in:
Antonio Borneo 2024-07-13 19:14:39 +02:00
parent 052a4a69b5
commit 5b7b77349c
4 changed files with 7 additions and 6 deletions

View File

@ -279,7 +279,8 @@ static int cortex_m_fast_read_all_regs(struct target *target)
/* because the DCB_DCRDR is used for the emulated dcc channel
* we have to save/restore the DCB_DCRDR when used */
if (target->dbg_msg_enabled) {
bool dbg_msg_enabled = target->dbg_msg_enabled;
if (dbg_msg_enabled) {
retval = mem_ap_read_u32(armv7m->debug_ap, DCB_DCRDR, &dcrdr);
if (retval != ERROR_OK)
return retval;
@ -332,7 +333,7 @@ static int cortex_m_fast_read_all_regs(struct target *target)
if (retval != ERROR_OK)
return retval;
if (target->dbg_msg_enabled) {
if (dbg_msg_enabled) {
/* restore DCB_DCRDR - this needs to be in a separate
* transaction otherwise the emulated DCC channel breaks */
retval = mem_ap_write_atomic_u32(armv7m->debug_ap, DCB_DCRDR, dcrdr);

View File

@ -5813,7 +5813,7 @@ static int target_create(struct jim_getopt_info *goi)
}
target->dbgmsg = NULL;
target->dbg_msg_enabled = 0;
target->dbg_msg_enabled = false;
target->endianness = TARGET_ENDIAN_UNKNOWN;

View File

@ -160,7 +160,7 @@ struct target {
struct watchpoint *watchpoints; /* list of watchpoints */
struct trace *trace_info; /* generic trace information */
struct debug_msg_receiver *dbgmsg; /* list of debug message receivers */
uint32_t dbg_msg_enabled; /* debug message status */
bool dbg_msg_enabled; /* debug message status */
void *arch_info; /* architecture specific information */
void *private_config; /* pointer to target specific config data (for jim_configure hook) */
struct target *next; /* next target in list */

View File

@ -164,7 +164,7 @@ static int add_debug_msg_receiver(struct command_context *cmd_ctx, struct target
(*p)->next = NULL;
/* enable callback */
target->dbg_msg_enabled = 1;
target->dbg_msg_enabled = true;
return ERROR_OK;
}
@ -225,7 +225,7 @@ int delete_debug_msg_receiver(struct command_context *cmd_ctx, struct target *ta
free(c);
if (!*p) {
/* disable callback */
target->dbg_msg_enabled = 0;
target->dbg_msg_enabled = false;
}
return ERROR_OK;
} else