cpu/cc26xx_cc13xx: Fix bogus array-bound warning [backport 2023.04] #19509
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GCC 12 create a bogus array out of bounds warning as it assumes that
because there is special handling for `uart == 0` and `uart == 1`,
`uart` can indeed be `1`. There is an `assert(uart < UART_NUMOF)` above
that would blow up prior to any out of bounds access.
In any case, optimizing out the special handling of `uart == 1` for
when `UART_NUMOF == 1` likely improves the generated code and fixes
the warning.
/home/maribu/Repos/software/RIOT/cc2650/cpu/cc26xx_cc13xx/periph/uart.c:88:8: error: array subscript 1 is above array bounds of 'uart_isr_ctx_t[1]' [-Werror=array-bounds]
88 | ctx[uart].rx_cb = rx_cb;
| ~~~^~~~~~
/home/maribu/Repos/software/RIOT/cc2650/cpu/cc26xx_cc13xx/periph/uart.c:52:23: note: while referencing 'ctx'
52 | static uart_isr_ctx_t ctx[UART_NUMOF];
| ^~~
/home/maribu/Repos/software/RIOT/cc2650/cpu/cc26xx_cc13xx/periph/uart.c:89:8: error: array subscript 1 is above array bounds of 'uart_isr_ctx_t[1]' [-Werror=array-bounds]
89 | ctx[uart].arg = arg;
| ~~~^~~~~~
/home/maribu/Repos/software/RIOT/cc2650/cpu/cc26xx_cc13xx/periph/uart.c:52:23: note: while referencing 'ctx'
52 | static uart_isr_ctx_t ctx[UART_NUMOF];
| ^~~
(cherry picked from commit d6499fa)
maribu
added
Area: cpu
|
OK, we will add this in but not create a new RC, if there is something else that comes up that is worth doing a point release it will be added. |
|
bors merge |
|
bors cancel |
|
Canceled. |
|
This should be merged into the release branch after the release is finished. |
|
Now that the release is done, bors merge |
|
bors merge |
|
Build succeeded: |
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Backport of #19504
Contribution description
GCC 12 create a bogus array out of bounds warning as it assumes that because there is special handling for
uart == 0anduart == 1,uartcan indeed be1. There is anassert(uart < UART_NUMOF)above that would blow up prior to any out of bounds access.In any case, optimizing out the special handling of
uart == 1for whenUART_NUMOF == 1likely improves the generated code and fixes the warning.Testing procedure
The actual change is a pretty obvious one-liner, so that code review and a green CI should be sufficient. If not, running any UART example app without regression should do.
Issues/PRs references
None