Array out-of-bounds checking problem caused by compilation optimization level - O2

[XiaoSenLuo]

Describe the bug
I compile the demo_threadx code with -O2 flag, but, tx_thread_system_suspend.c is occur a error about array bounds. I try to change the level of optimize to -O1, and then there are no thing happened, anything look like good.

The reason is that _tx_thread_lowest_set_bit_calculate function can return a value beyond the value of TX_THREAD_SMP_MAX_CORES - 1, and its parameter "map" should be limited.

my method is to modify the macro definition TX_LOWEST_SET_BIT_CALCULATE,
the original definition:

#define TX_LOWEST_SET_BIT_CALCULATE (m, b) (b) = _tx_thread_lowest_set_bit_calculate((m)); 

New definition:

#define TX_LOWEST_SET_BIT_CALCULATE(m, b) (b) = _tx_thread_lowest_set_bit_calculate((m) &TX_THREAD_SMP_CORE_MASK);

I don't know what the impact of such a change will be, and I hope someone can tell me, thanks.

Please also mention any information which could help others to understand
the problem you're facing:

• Cortex-A9, zynq 7000?
  -Threadx V6.4.3.202503?
• xilinx arm-none-eabi-gcc 12.2?

This is an error message from the terminal, I hope it helps you

C:\UserProgram\Xilinx\Vitis\2023.2\gnu\aarch32\nt\gcc-arm-none-eabi\bin\arm-none-eabi-gcc.exe -DNDEBUG -DSHAREABLE_DDR=1 -DTARGET_FPU_VFP=1 -DTX_ENABLE_VFP_SUPPORT=1 -DTX_INCLUDE_USER_DEFINE_FILE -DTX_THREAD_SMP_CORE_MASK=0x03 -DTX_THREAD_SMP_DEFAULT_WAKEUP_LOGIC -DTX_THREAD_SMP_MAX_CORES=2 -DTX_THREAD_SMP_ONLY_CORE_0_DEFAULT -DXDEBUG_WARNING -D_GNU_SOURCE -IC:/UserTemp/test_7020/ps/common/os/threadx_zynq/ports_smp/cortex_a9_smp/gnu/inc -IC:/UserTemp/test_7020/ps/common/os/threadx_zynq -IC:/UserTemp/test_7020/ps/cmake-build-release-xilinx-vitis/common/os/threadx/custom_inc -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/coresightps_dcc_v1_9/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/cpu_cortexa9_v2_12/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/ddrps_v1_2/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/dmaps_v2_9/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/devcfg_v3_8/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/gpiops_v3_12/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/emacps_v3_19/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/scugic_v5_2/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/scutimer_v2_5/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/scuwdt_v2_5/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/sdps_v4_2/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/ttcps_v3_18/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/uartps_v3_13/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/xadcps_v2_7/src -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/standalone_v9_0/src/common -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/standalone_v9_0/src/arm/common -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/libsrc/standalone_v9_0/src/arm/cortexa9 -IC:/UserTemp/test_7020/ps/s19_platform/ps7_cortexa9_0/standalone_domain/bsp/ps7_cortexa9_0/include -isystem C:/UserTemp/test_7020/ps/common/os/threadx/common_smp/inc -O3 -DNDEBUG -std=gnu11 -fdiagnostics-color=always -mcpu=cortex-a9 -mfloat-abi=hard -marm -mfpu=neon-vfpv4 -Wall -Wextra -fno-tree-loop-distribute-patterns -fdata-sections -ffunction-sections -O2 -Werror -pedantic -fmessage-length=0 -fsigned-char -Wunused -Wuninitialized -Wmissing-declarations -Wconversion -Wpointer-arith -Wshadow -Wlogical-op -Waggregate-return -Wfloat-equal -MD -MT common/os/threadx/CMakeFiles/threadx.dir/common_smp/src/tx_thread_system_suspend.c.obj -MF common\os\threadx\CMakeFiles\threadx.dir\common_smp\src\tx_thread_system_suspend.c.obj.d -o common/os/threadx/CMakeFiles/threadx.dir/common_smp/src/tx_thread_system_suspend.c.obj -c C:/UserTemp/test_7020/ps/common/os/threadx/common_smp/src/tx_thread_system_suspend.c
In file included from C:/UserTemp/test_7020/ps/common/os/threadx/common_smp/src/tx_thread_system_suspend.c:31:
In function '_tx_thread_smp_remap_solution_find',
    inlined from '_tx_thread_system_suspend' at C:/UserTemp/test_7020/ps/common/os/threadx/common_smp/src/tx_thread_system_suspend.c:777:57:
C:/UserTemp/test_7020/ps/common/os/threadx/common_smp/inc/tx_thread.h:1336:37: error: array subscript 2 is above array bounds of 'TX_THREAD *[2]' {aka 'struct TX_THREAD_STRUCT *[2]'} [-Werror=array-bounds]
 1336 |         _tx_thread_smp_schedule_list[core] =     last_thread;
      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
C:/UserTemp/test_7020/ps/common/os/threadx/common_smp/inc/tx_thread.h: In function '_tx_thread_system_suspend':
C:/UserTemp/test_7020/ps/common/os/threadx/common_smp/inc/tx_thread.h:187:45: note: while referencing '_tx_thread_smp_schedule_list'
  187 | THREAD_DECLARE  TX_THREAD *                 _tx_thread_smp_schedule_list[TX_THREAD_SMP_MAX_CORES];
      |                                             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1.exe: all warnings being treated as errors

[XiaoSenLuo]

This modification looks like threadx doesn't work.

[fdesbiens]

Hi @XiaoSenLuo.

My apologies; this issue slipped under my radar. I will ask a team member to have a look and get back to you.