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deadprogram
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tinygo_longjmp ended with a j instruction, which reaches only 128 KB. picolibc puts longjmp in the plain .text group of the linker script, while all TinyGo code goes into the .text.* group after it. In a large program the two are more than 128 KB apart and the link stops with an out of range R_XTENSA_SLOT0_OP relocation. Small programs link correctly, thus the smoke tests do not find this. Load the address of longjmp from a literal and jump to it with jx. The literal carries an R_XTENSA_32 relocation, which has no range limit. Place the literal by hand in the same section as the code. Automatic literals go into a separate section, which this tree already records as a cause of bad l32r offsets with LLVM 22 and lld. See the comments in src/device/esp/esp32.S and src/device/esp/esp32s3.S. Keep the jump instead of a call. tinygo_longjmp has no entry instruction and runs in the register window of its caller. A call would rotate the window a second time and give longjmp bad arguments. a8 is free in both ABIs. In the windowed ABI it becomes a0 of longjmp, which longjmp overwrites at once from the jmp_buf. In the call0 ABI it is a scratch register and longjmp reads only a2 and a3. The recover test passes on ESP32 in QEMU and on ESP32-S3 hardware.