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https://github.com/imjasonh/nescript
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a5f508a678
The `seg.ooffs` field in our ca65 .dbg output was off by 16 — it was emitting the PRG-relative fixed-bank offset when ca65's convention (and Mesen's DbgImporter.cs:301 math: `Address = val - seg.start + ooffs - headerSize`) expects the raw output-file offset, *including* the iNES header. The practical consequence: every label Mesen resolved via the .dbg was 16 bytes short of its true PRG offset, which silently corrupted source-line mapping for the first bytes of each function. Fix is a one-liner — drop the `saturating_sub(16)` and feed `linked.fixed_bank_file_offset` straight into the ooffs field. Unit tests in debug_symbols.rs updated to assert the new values (ooffs=16 for NROM, 16+16K*N for banked). The Mesen probe (`tests/mesen/probe.lua`) is expanded in the same change, because the sabotage test that caught this bug is also the cleanest demonstration the probe is working: * checks all four entry-point labels resolve and land inside the fixed bank's CPU window ($C000-$FFFF); * asserts the linker's relative ordering (main_loop < Main_frame < nmi); * registers a startFrame callback, waits three frames, and verifies PC is still in the fixed bank + that `emu.read(main_loop.address, nesPrgRom)` returns 0xA5 (the LDA-zp opcode the runtime always places as main_loop's first instruction). The 0xA5 constant is what catches the ooffs regression — a less-specific "not 0xFF" check coincidentally passed even with ooffs=0 because the shifted address still landed on real code. Verified locally by running the probe against hello_sprite's ROM with four different `.dbg` mutations and confirming each triggers the expected exit code. https://claude.ai/code/session_01DfN3pKJLryr7vvNFBpcqmC |
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| emulator | ||
| integration | ||
| mesen | ||
| integration_test.rs | ||