// ltoProbe.c - Phase 5.2 ThinLTO smoke probe.
// Calls a helper compiled in a SEPARATE TU (ltoProbeHelper.c) via the
// scripts/ltoLink.sh driver.  The helper returns a constant; under LTO
// the value gets constant-folded into main and printf sees the literal.
// In the non-LTO build, the call survives as a real jsl long.
//
// Build commands (LTO):
//   CC=tools/llvm-mos-build/bin/clang
//   $CC --target=w65816 -I runtime/include -O2 -ffunction-sections \
//       -emit-llvm -c demos/ltoProbe.c -o /tmp/ltoProbe.bc
//   $CC --target=w65816 -I runtime/include -O2 -ffunction-sections \
//       -emit-llvm -c demos/ltoProbeHelper.c -o /tmp/ltoProbeHelper.bc
//   bash scripts/ltoLink.sh -o /tmp/ltoProbeMerged.o \
//       /tmp/ltoProbe.bc /tmp/ltoProbeHelper.bc
//   ... then link /tmp/ltoProbeMerged.o with crt0Gno + libcGno + ...
//   via tools/link816, wrap with tools/omfEmit, run under runInGno.sh.
#include <stdint.h>
#include <stdio.h>

extern int computeMagic(void);

int main(int argc, char **argv) {
    int m = computeMagic();
    printf("magic=0x%x\n", m);
    *(volatile uint16_t *)0x025000UL = (uint16_t)m;
    for (volatile unsigned long i = 0; i < 100000UL; i++) {}
    return 0;
}