Fixed the garbage _tx_initialize_unused_memory in the GNU Cortex-A ports - #726
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…level initialization, so _tx_initialize_unused_memory now holds the first free address instead of garbage __top_of_ram is a linker-defined symbol whose address is the value of interest, so LDR x1, =__top_of_ram already loads the top of RAM. The following LDR x1, [x1] read whatever happened to be stored there and handed that garbage to _tx_initialize_unused_memory. The Arm Compiler ports are not affected: they load a literal .quad that holds the address, so the dereference is correct there. The SMP GNU ports already had the correct form; this aligns the remaining GNU ports with them. Assisted-by: Copilot (Opus 5) <noreply@github.com>
This was referenced Sep 10, 2026
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Fixes #435
LDR x1, =__top_of_ramalready loads the top of RAM, so theLDR x1, [x1]that followed read whatever sat at that address and left
_tx_initialize_unused_memoryholding garbage.Dropped that instruction from the 13 non-SMP GNU Cortex-A ports, the ARMv8-A
source they are generated from, and the two Cortex-A35 module examples. The SMP
GNU ports already had the correct form, and the Arm Compiler ports are
unaffected -- their symbol really does need the dereference.
scripts/check_ports.shpasses and thegnuCI job build-verifies the AArch64ports. Not run on hardware.