target/espressif: fix clang report on use of garbage value

When the function xtensa_queue_dbg_reg_read() returns error, the
array 'tmp' remains not initialized and scan-build complains while
computing buf_get_u32() that:
	Result of operation is garbage or undefined

Check the returned value of xtensa_queue_dbg_reg_read() and
propagate it.

Change-Id: If0aaad068b97ef0a76560e262d16429afd469585
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Fixes: 8d1dcf293a0c ("target/espressif: add application tracing functionality over JTAG")
Reviewed-on: https://review.openocd.org/c/openocd/+/7607
Tested-by: jenkins
Reviewed-by: Erhan Kurubas <erhan.kurubas@espressif.com>

diff --git a/src/target/espressif/esp_xtensa_apptrace.c b/src/target/espressif/esp_xtensa_apptrace.c
index dfb846da07d858ef2ad01d792eea44c59a341ced..5741ab030833ee76a59d4cbeac99ff931aee9747 100644 (file)
--- a/src/target/espressif/esp_xtensa_apptrace.c
+++ b/src/target/espressif/esp_xtensa_apptrace.c
@@ -242,9 +242,11 @@ int esp_xtensa_apptrace_status_reg_read(struct target *target, uint32_t *stat)
        struct xtensa *xtensa = target_to_xtensa(target);
        uint8_t tmp[4];
 
-       xtensa_queue_dbg_reg_read(xtensa, XTENSA_APPTRACE_STAT_REG, tmp);
+       int res = xtensa_queue_dbg_reg_read(xtensa, XTENSA_APPTRACE_STAT_REG, tmp);
+       if (res != ERROR_OK)
+               return res;
        xtensa_dm_queue_tdi_idle(&xtensa->dbg_mod);
-       int res = xtensa_dm_queue_execute(&xtensa->dbg_mod);
+       res = xtensa_dm_queue_execute(&xtensa->dbg_mod);
        if (res != ERROR_OK) {
                LOG_ERROR("Failed to exec JTAG queue!");
                return res;