fix: change stack alignment from 4 to 8 bytes for all STM32 targets

[finnyoun9]

Summary

Fixes stack alignment issue for STM32 targets (Issue #7527).

The .stack section in STM32 linker scripts was aligned to 4 bytes, causing issues with 8-byte types (e.g. double) being passed via variadic functions. This PR changes ALIGN(4) to ALIGN(8) in the .stack section for all affected STM32 BSPs.

Closes #7527

Changes

• Changed ALIGN(4) to ALIGN(8) in .stack section of 13 STM32 linker scripts
• Does NOT affect .text or .bss sections (they remain at ALIGN(4) — correct for 4-byte instructions/data)

Affected files

• bsp/stm32/libraries/templates/stm32f2xx/board/linker_scripts/link.lds
• bsp/stm32/libraries/templates/stm32l1xx/board/linker_scripts/link.lds
• bsp/stm32/libraries/templates/stm32mp1xx/board/linker_scripts/link.lds
• bsp/stm32/stm32f401-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32f405-smdz-breadfruit/board/linker_scripts/link.lds
• bsp/stm32/stm32f410-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32f446-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32h743-openmv-h7plus/board/linker_scripts/link.lds
• bsp/stm32/stm32h743-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32l432-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32l433-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32l4r9-st-eval/board/linker_scripts/link.lds
• bsp/stm32/stm32u585-iot02a/board/linker_scripts/link.lds

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[github-actions]

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[github-actions]

📌 Code Review Assignment

🏷️ Tag: bsp_stm32

Reviewers: @Liang1795 @hamburger-os @wdfk-prog

Changed Files (Click to expand)

• bsp/stm32/libraries/templates/stm32f2xx/board/linker_scripts/link.lds
• bsp/stm32/libraries/templates/stm32l1xx/board/linker_scripts/link.lds
• bsp/stm32/libraries/templates/stm32mp1xx/board/linker_scripts/link.lds
• bsp/stm32/stm32f401-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32f405-smdz-breadfruit/board/linker_scripts/link.lds
• bsp/stm32/stm32f410-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32f446-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32h743-openmv-h7plus/board/linker_scripts/link.lds
• bsp/stm32/stm32h743-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32l432-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32l433-st-nucleo/board/linker_scripts/link.lds
• bsp/stm32/stm32l4r9-st-eval/board/linker_scripts/link.lds
• bsp/stm32/stm32u585-iot02a/board/linker_scripts/link.lds

🏷️ Tag: bsp_stm32h743-st-nucleo

Reviewers: @LittleGreyG

Changed Files (Click to expand)

• bsp/stm32/stm32h743-st-nucleo/board/linker_scripts/link.lds

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📊 Current Review Status (Last Updated: 2026-06-28 21:43 CST)

• ⌛ @Liang1795 Pending Review
• ⌛ @LittleGreyG Pending Review
• ⌛ @hamburger-os Pending Review
• ⌛ @wdfk-prog Pending Review

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[LittleGreyG]

对于h7来说可提高浮点算法性能。建议修改。

[wdfk-prog]

• Arm® 架构咨询备忘录的 ABI – SP 在进入符合 AAPCS 的函数时必须为 8 字节对齐
• 提交进行了大规模删除这个不对,需要修改

[github-actions]

MemBrowse Memory Report

No memory changes detected for:

• stm32f407-rt-spark
• stm32l475-atk-pandora-llvm