Add native Portduino malloc shim

[h3lix1]

Add Darwin malloc.h Shim For Portduino

Branch: codex/native-portduino-malloc-shim

Target: meshtastic/firmware:develop

Why

Some native macOS build paths encounter code that includes <malloc.h>, which is a Linux header name. On Darwin, the equivalent allocator declarations live in <malloc/malloc.h>, and memalign() is not provided directly.

What

This adds a small Portduino-local compatibility header:

• On macOS, include <malloc/malloc.h> and <stdlib.h>.
• Provide memalign() through posix_memalign().
• On non-Apple platforms, defer to the next real <malloc.h> with include_next.

The file is scoped to variants/native/portduino, so firmware targets and Linux native builds keep their existing behavior.

How

flowchart LR
    LGFX["Code includes <malloc.h>"] --> Shim["variants/native/portduino/malloc.h"]
    Shim --> Apple{"__APPLE__?"}
    Apple -->|yes| Darwin["malloc/malloc.h + posix_memalign"]
    Apple -->|no| Native["include_next <malloc.h>"]

Loading

Validation

• trunk fmt variants/native/portduino/malloc.h
• ~/.platformio/penv/bin/platformio run -e native-macos

The native build progressed past the original <malloc.h> failure.

Test Notes

No unit test is needed for this header shim. The useful check is a macOS native build in an environment with the documented native prerequisites installed.

[thebentern]

@h3lix1 looks good. You still have it in draft for a reason?

[github-actions]

⚡ Try this PR in the Web Flasher

Warning

This is an automated, unreviewed CI test build. Back up your device configuration
before flashing, and only flash devices you are able to recover.

Supported boards built by this PR (21)

	Device	Board	Platform
	Crowpanel Adv 3.5 TFT	elecrow-adv-35-tft	esp32-s3
	Heltec HT62	heltec-ht62-esp32c3-sx1262	esp32-c3
	Heltec Mesh Node 096	heltec-mesh-node-t096	nrf52840
	Heltec Mesh Node T1	heltec-mesh-node-t1	nrf52840
	Heltec Mesh Node T114	heltec-mesh-node-t114	nrf52840
	Heltec V3	heltec-v3	esp32-s3
	Raspberry Pi Pico	pico	rp2040
	Raspberry Pi Pico W	picow	rp2040
	RAK WisBlock 11200	rak11200	esp32
	RAK WisBlock 11310	rak11310	rp2040
	RAK3312	rak3312	esp32-s3
	RAK WisBlock 4631	rak4631	nrf52840
	Seeed Xiao NRF52840 Kit	seeed_xiao_nrf52840_kit	nrf52840
	Seeed Xiao ESP32-S3	seeed-xiao-s3	esp32-s3
	Station G2	station-g2	esp32-s3
	Station G3	station-g3	esp32-s3
	LILYGO T-Deck	t-deck-tft	esp32-s3
	LILYGO T-Echo	t-echo	nrf52840
	LILYGO T-Echo Plus	t-echo-plus	nrf52840
	LilyGo T3-C6	tlora-c6	esp32-c6
	Seeed SenseCAP T1000-E	tracker-t1000-e	nrf52840

Build artifacts expire on 2026-07-10. Updated for e513d80.

[github-actions]

Firmware Size Report

22 targets | vs develop: 22 decreased, net -12,412 (-12.1 KB)

Target	Size	vs develop
heltec-v4	2,255,360	📉 -848
rak3312	2,241,616	📉 -848
seeed-xiao-s3	2,245,600	📉 -832
t-eth-elite	2,461,200	📉 -832
heltec-v3	2,234,848	📉 -816

Show 17 more target(s)

Target	Size	vs develop
t-deck-tft	3,781,216	📉 -816
station-g2	2,246,160	📉 -768
station-g3	2,236,576	📉 -768
rak11200	1,830,464	📉 -752
picow	1,220,192	📉 -668
pico	759,928	📉 -664
rak11310	782,520	📉 -664
seeed_xiao_rp2040	758,144	📉 -664
pico2w	1,196,796	📉 -580
pico2	747,920	📉 -552
seeed_xiao_rp2350	746,072	📉 -552
elecrow-adv-35-tft	3,387,920	📉 -208
heltec-vision-master-e213-inkhud	2,195,392	📉 -176
wio-e5	232,564	📉 -112
rak3172	180,200	📉 -100
heltec-ht62-esp32c3-sx1262	2,106,880	📉 -96
tlora-c6	2,340,784	📉 -96

---

Updated for be211ba

[Copilot]

Pull request overview

Adds a Portduino-local malloc.h compatibility shim so native macOS (Darwin) builds can compile code that includes the Linux header name <malloc.h>, by redirecting to Darwin’s <malloc/malloc.h> and providing a memalign() implementation.

Changes:

• Introduces variants/native/portduino/malloc.h to satisfy <malloc.h> includes in native Portduino builds.
• On __APPLE__, includes <malloc/malloc.h>/<stdlib.h> and implements memalign() via posix_memalign().
• On non-Apple platforms, defers to the real system <malloc.h> via #include_next.

[h3lix1]

@thebentern will need a re-approval after applying the thing copilot recommended.