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command-line-interfacepreprocessorconditional-compilationyosys

Conditional compilation in ice40_synth using yosys?

I'm currently compiling a bitstream for my project in a Makefile.

For the non-debug version of the build I use the following command:

yosys -p "synth_ice40 -blif $@ -top system" $^

And for the debug version I use:

yosys -p "verilog_defaults -add -DDEBUG; synth_ice40 -blif $@ -top system" $^

In the case of the debug build, the command completes, but `DEBUG is not defined when the verilog is read/parsed.

Does verilog_defaults apply to ice40_synth? And if not, is there a way to achieve this without replicating ice40_synth in a script?

Solution

  • Source files specified as command line arguments are read before the commands in -p are executed. Thus, the verilog_defaults -add has no effect on parsing of $^.

    One way of doing what you want is by manually setting the front-end + options to be used for command line arguments with -f:

    yosys -f "verilog -DDEBUG" -p "synth_ice40 -blif $@ -top system" $^