Fix address offset bug after STRUCT variables #9
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- Add 2-byte alignment after STRUCT variables in _AddStructVariable() - Prevents subsequent variables from being placed at incorrect addresses - Fixes issue where variables after STRUCTs were offset by incorrect bit positions - Ensures proper STEP 7 memory layout compliance Resolves address calculation errors where variables following STRUCT definitions were assigned wrong DB addresses (e.g. DB3200:0.3 instead of DB3200:2.0).
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Problem
Variables defined after STRUCT variables were assigned incorrect memory addresses, causing a systematic offset in the exported symbol addresses.
Root Cause
After parsing STRUCT variables, the parser did not align the bit address counter to the next 2-byte boundary before continuing with subsequent variables. This caused variables following STRUCTs to be placed at incorrect memory positions.
Example
ix_AutomaticStartgot addressDB320:0.3instead ofDB320:2.0DB320:2.0as expected in STEP 7Solution
Added 2-byte alignment (
_AlignUp(2 * 8)) at the end of_AddStructVariable()to ensure subsequent variables start at correct memory boundaries, maintaining STEP 7 memory layout compliance.Testing
Files Changed
src/EnlyzeS7PLib/src/CMc5codeParser.cpp: Added alignment after STRUCT processing