layout: don't give the NOLOAD .stack section a flash LMA - #595
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The .stack section is NOLOAD but used `> RAM AT > FLASH`. Because it precedes .data and was also assigned a flash load address, the linker reserved stack-sized space in the flash LMA layout, leaving a gap between .rodata and .data. elf2tab pads gaps between load segments, so this gap was emitted as zero bytes into the TBF, inflating the flash image for stack space that is never loaded from flash. Drop `AT > FLASH` so .stack's LMA equals its RAM VMA and .data follows .rodata with no gap. rt_header uses LOADADDR(.data) and _sram_origin/_stack_top are VMAs, so ARM/RISC-V behavior should be unchanged. Signed-off-by: Akshatha Udayashankar <akudayas@microsoft.com>
jrvanwhy
approved these changes
Jul 4, 2026
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The .stack section is NOLOAD but used
> RAM AT > FLASH. Because it precedes .data and was also assigned a flash load address, the linker reserved stack-sized space in the flash LMA layout, leaving a gap between .rodata and .data. elf2tab pads gaps between load segments, so this gap was emitted as zero bytes into the TBF, inflating the flash image for stack space that is never loaded from flash.Drop
AT > FLASHso .stack's LMA equals its RAM VMA and .data follows .rodata with no gap. rt_header uses LOADADDR(.data) and _sram_origin/_stack_top are VMAs, so ARM/RISC-V behavior should be unchanged.