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vsim does not accept -modelsimini parameter on Windows

I'm using the command line argument -modelsimini <modelsim.ini> to specify my own modelsim.ini file for most QuestaSim / ModelSim executables.

This works perfectly fine on Linux for vcom and vsim, as well as for vcom on Windows. But the Windows vsim aborts and throws an error:

C:\Mentor\QuestaSim64\10.4c\win64\vsim.exe -do "do D:/git/PoC/sim/vSim.batch.tcl" -c -modelsimini D:\git\PoC\temp\precompiled\vsim\modelsim.ini -error 3473 -t 1fs test.arith_prng_tb
Reading C:/Mentor/QuestaSim64/10.4c/tcl/vsim/pref.tcl

# 10.4c

# ** Error: (vsim-7) Failed to open -modelsimini file "{D:\git\PoC\temp\precompiled\vsim\modelsim.ini}" in read mode.
#
# Invalid argument. (errno = EINVAL)
# Error loading design
Error loading design
# Errors: 1, Warnings: 0

The modelsim.ini files exists and has the following content:

[Library]
others = $MODEL_TECH/../modelsim.ini

(This file will contain more lines if vendor tools add their library mappings.)

How can I pass my own modelsim.ini configuration file to vsim.exe?

Solution

  • It is questionable whether this should be considered as a bug or not because TCL requires that file names are specified with forward slashes instead of backward slashes. Of course, one would expect that file-names are handled the same way when calling vcom or vsim. So the solution from this viewpoint is to specify the path with forward slashes:

    C:\Mentor\QuestaSim64\10.4c\win64\vsim.exe -do "do D:/git/PoC/sim/vSim.batch.tcl" -c -modelsimini D:/git/PoC/temp/precompiled/vsim/modelsim.ini -error 3473 -t 1fs test.arith_prng_tb

    Checked it here with ModelSim 10.1d under Windows and a modelsim.ini in my temporary directory.

    Some experiments under the vsim TCL console reveals that -modelsimini file-name is handled differently by the vcom and vsim commands. At first a backslash indicates an escape sequence, a \t in the file-name is expanded to a tab for example:

    vcom -modelsimini c:\tmp\modelsim.ini test.vhdl
# ** Error: (vcom-7) Failed to open -modelsimini file "c:   mpmodelsim.ini" in read mode.
# 
# Invalid argument. (errno = EINVAL)
# D:/altera/13.1_web/modelsim_ase/win32aloem/vcom failed.

    To prevent this, the argument can be put in curly braces {} for example:

    vcom -modelsimini {c:\tmp\modelsim.ini} test.vhdl
# ** Error: (vcom-7) Failed to open -modelsimini file "c:\tmp\modelsim.ini" in read mode.
# 
# No such file or directory. (errno = ENOENT)
# D:/altera/13.1_web/modelsim_ase/win32aloem/vcom failed.

    I specified a non-existent file, so that one can see the expansion. If I create the file c:\tmp\modelsim.ini, vcom will proceed as expected. Yes, backslashes in file-names are allowed here.

    If we give the same arguments to vsim, the error messages (and the actual behaviour) will be different:

    vsim -modelsimini c:\tmp\modelsim.ini test
# vsim -modelsimini {{c:    mpmodelsim.ini}} test 
# ** Error: (vsim-7) Failed to open -modelsimini file "{c:  mpmodelsim.ini}" in read mode.
# 
# No such file or directory. (errno = ENOENT)
# Error loading design

vsim -modelsimini {c:\tmp\modelsim.ini} test
# vsim -modelsimini {{c:\tmp\modelsim.ini}} test 
# ** Error: (vsim-7) Failed to open -modelsimini file "{c:\tmp\modelsim.ini}" in read mode.
# 
# Invalid argument. (errno = EINVAL)
# Error loading design

    The file-name argument will be processed the same way as before. But then the vsim script adds another pair of curly-braces around the expanded argument. This behavior should be considered as a bug, because it does not make any sense. vsim finally looks for a file called {c:\tmp\modelsim.ini} which can never be found on a Windows file system. In your error message the file-name is also enclosed by curly braces.