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Last June, someone asked about how command line symbols defined for both the assembler and the C compiler could be referenced within a conditional (if) statement within a universal shared header file. A company rep said they'd forward this to the tech team for advice. Whatever happened? The issue is this: Symbols of identical name specified on the command line for the assembler and the C compiler end up being unique symbols. Those specified for the assembler are defined as per a "$set" directive and are visible only to the assembler. Those specified for the C compiler are defined as per a "#define" directive and are only visible when running the compiler. In other words, there is no way to define a symbol on the A51 assembler command line that will be visible to the C preprocessor within the assembler. Symbols defined this way are only visible to "$if" statements. PROBLEM: A universal header file containing an "#ifdef SYMBOL" conditional branch will work within C modules, but will not work within assembler modules because the assembler's C preprocessor WILL NOT recognize the referenced symbol and will thus test false. Example:
#ifdef SYMBOL #include <me.h> #endif
#define SYMBOL
P.S. For interested parties, the way we are handling this issue today is to maintain essentially identical ".inc" and ".h" files for the desired headers, thus, totally defeating the desire to maintain a SINGLE header file. The "GIZMO.inc" files are included in assembler modules and the "GIZMO.h" files are included in C modules. The ".inc" contains '$if' logic (and '$include', etc.) and the ".h" contains '#ifdef' logic and (and '#include', etc.) This is obviously suboptimal and mistakes happen.