Description
An exported project to LPCXpresso IDE (GCC_CR build) doesn't reach to the main() function for baremetal (non-RTOS) build.
Automate test result of the LPC1768 is below:
Test summary:
+---------+---------+-----------+-------------+---------------------------------------+--------------------+---------------+-------+
| Result | Target | Toolchain | Test ID | Test Description | Elapsed Time (sec) | Timeout (sec) | Loops |
+---------+---------+-----------+-------------+---------------------------------------+--------------------+---------------+-------+
| TIMEOUT | LPC1768 | GCC_CR | DTCT_1 | Simple detect test | 20.07 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | EXAMPLE_1 | /dev/null | 20.07 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_10 | Hello World | 20.07 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_11 | Ticker Int | 40.33 | 20 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_12 | C++ | 20.08 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_16 | RTC | 30.25 | 15 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_2 | stdio | 40.34 | 20 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_22 | Semihost | 20.14 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_23 | Ticker Int us | 30.25 | 15 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_24 | Timeout Int us | 30.25 | 15 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_25 | Time us | 30.23 | 15 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_26 | Integer constant division | 20.08 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_34 | Ticker Two callbacks | 30.22 | 15 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_37 | Serial NC RX | 20.1 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_38 | Serial NC TX | 20.12 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_A1 | Basic | 20.07 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_A18 | Interrupt vector relocation | 20.09 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_A2 | Semihost file system | 20.12 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_A21 | Call function before main (mbed_main) | 20.13 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_A9 | Serial Echo at 115200 | 20.09 | 10 | 0/1 |
| TIMEOUT | LPC1768 | GCC_CR | MBED_BUSOUT | BusOut | 30.21 | 15 | 0/1 |
| OK | LPC1768 | GCC_CR | RTOS_1 | Basic thread | 12.69 | 15 | 1/1 |
| OK | LPC1768 | GCC_CR | RTOS_2 | Mutex resource lock | 12.84 | 20 | 1/1 |
| OK | LPC1768 | GCC_CR | RTOS_3 | Semaphore resource lock | 9.81 | 20 | 1/1 |
| OK | LPC1768 | GCC_CR | RTOS_4 | Signals messaging | 7.78 | 20 | 1/1 |
| OK | LPC1768 | GCC_CR | RTOS_5 | Queue messaging | 3.7 | 20 | 1/1 |
| OK | LPC1768 | GCC_CR | RTOS_6 | Mail messaging | 3.71 | 20 | 1/1 |
| OK | LPC1768 | GCC_CR | RTOS_7 | Timer | 12.62 | 15 | 1/1 |
| OK | LPC1768 | GCC_CR | RTOS_8 | ISR (Queue) | 7.81 | 20 | 1/1 |
+---------+---------+-----------+-------------+---------------------------------------+--------------------+---------------+-------+
Result: 8 OK / 21 TIMEOUT
Completed in 732.83 sec
This was because the software_init_hook() function was defined here with strong (non-weak) symbol by this change.
Original code in the reset vector startup code for GCC_CR is below:
extern "C" void software_init_hook(void) __attribute__((weak));
AFTER_VECTORS void ResetISR(void) {
// snip
SystemInit();
if (software_init_hook) // give control to the RTOS
software_init_hook(); // this will also call __libc_init_array
else {
__libc_init_array();
main();
}
while (1) {;}
}
The software_init_hook symbol is now defined as strong rather than weak, therefore if (software_init_hook) statement is always true even an mbed-rtos library is not linked. i.e. baremetal project.
I tried to use a software_init_hook_rtos symbol instead which is weakly defined in retarget.cpp, but this was strongly linked into the ResetISR startup code because they were in the same static library. See: http://stackoverflow.com/questions/23079997/override-weak-symbols-in-static-library
When I use pre_main symbol which is weakly defined in other static library (mbed-rtos) and it works as expected. I will make PR once my local test has been completed.