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Altera_Forum's avatar
Altera_Forum
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21 years ago

Lots of warnings during VHDL compilation

Hi,

as I am compiling a simple design, containing a Nios-II processor, the Quartus-II VHDL compiler spews quite some warning messages. A snippet:

info: running quartus ii analysis & synthesis

info: version 4.2 build 156 11/29/2004 sj web edition

info: processing started: sun feb 06 18:52:56 2005

info: command: quartus_map --import_settings_files=on --export_settings_files=off first_nios -c first_nios

... lines ommitted for clarity ...

warning: vhdl process statement warning at cpu_jtag_debug_module.vhd(236): signal "usr1" is read inside the process statement but isn't in the process statement's sensivitity list

warning: vhdl process statement warning at cpu_jtag_debug_module.vhd(236): signal "ena" is read inside the process statement but isn't in the process statement's sensivitity list

warning: vhdl process statement warning at cpu_jtag_debug_module.vhd(239): signal "usr1" is read inside the process statement but isn't in the process statement's sensivitity list

..

info: power-up level of register "rollator:inst|reset_clk_domain_synch_module:reset_clk_domain_synch|data_in_d1" is not specified -- using power-up level of high to minimize register

warning: reduced register "rollator:inst|reset_clk_domain_synch_module:reset_clk_domain_synch|data_in_d1" with stuck data_in port to stuck value vcc

...

..And a lot more warnings having to do with signals being stuck at either VCC or GND.

Now my question is: is it normal for a Nios-II design to generate a lot of VHDL compilation warnings ? Or am I making a mistake here (certainly would not rule this out) ? What are your experiences ?

Bye,

Roland.

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    21 years ago

    A lot of the time you get warnings saying buses being truncated and other messages of the sorts. I basically turn on my blinders for warnings like that since those are just telling you things are optimized out that are not necessary. In short I wouldn't worry about it unless your design doesn't work.

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    21 years ago

    Yes, it is normal, NiosII gives a lot of warnings like those you've mentioned. My opinion is that they are useful for user logic, but I don't see the point in displaying them for proven/tested code like NiosII which a user doesn't even have source-code access to. Some options to enable/disable different warning levels would be nice to have.