---
name: "vppreproc"
section: "1p"
platform: "linux"
package: "libverilog-perl"
version: "3.482-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/vppreproc"
---

# vppreproc(1p)

Preprocess Verilog code using verilog-perl

## NAME

vppreproc - Preprocess Verilog code using verilog-perl

## SYNOPSIS

```
  vppreproc --help
  vppreproc [verilog_options] [-o filename] [verilog_files.v...]
```

## DESCRIPTION

Vppreproc reads the Verilog files passed on the command line and outputs preprocessed output to standard out or the filename passed with **-o**.

Note vppreproc was named vppp until release 3.100, so if you're looking for vppp, this is the right replacement.  The vppp name conflicted with another non-Verilog related tool.

## VERILOG ARGUMENTS

The following arguments are compatible with GCC, VCS and most Verilog programs.

- \+define+*var*+*value* =item -D*var*=*value*

  Defines the given preprocessor symbol.

- \-f *file*

  Read the specified file, and act as if all text inside it was specified as command line parameters.

- \-f *file*

  Read the specified file, and act as if all text inside it was specified as command line parameters.  Any relative paths are relative to the current directory.

- \+incdir+*dir* =item -I*dir*

  Add the directory to the list of directories that should be searched for include directories or libraries.

- \+libext+*ext*+*ext*...

  Specify the extensions that should be used for finding modules.  If for example module *x* is referenced, look in *x*.*ext*.

- \-y *dir*

  Add the directory to the list of directories that should be searched for include directories or libraries.

## VPPREPROC ARGUMENTS

- \--help

  Displays this message and program version and exits.

- \--o *file*

  Use the given filename for output instead of stdout.

- \--dump-defines

  Suppress normal output, and instead print a list of all defines existing at the end of processing the input file.

- \--noblank

  Removes empty lines from the output.  Should be used with --noline, as if correct line numbers are needed, blank lines must be preserved for proper accounting by the program reading the output of vppreproc.

- \--nocomment

  Remove comments.

- \--noline

  Remove \`line directives.

- \-P

  Same as --noline --noblank, similar to "GCC -P" behavior.

- \--pedantic

  Rigorously obey the Verilog spec.  This disables the \`error feature, and may disable other features that are not specified in the approved language reference manual. Defaults false.

- \--simple

  Requests simple output, an alias for --noline, --nocomment and --noblank.

- \--synthesis

  Define SYNTHESIS, and ignore text between "ambit", "pragma", "synopsys" or "synthesis" translate\_off and translate\_on meta comments.  Note using metacomments is discouraged as they have led to silicon bugs (versus ifdef SYNTHESIS); see \<https://www.veripool.org/papers/TenIPEdits\_SNUGBos07\_paper.pdf\>.

- \--version

  Displays program version and exits.

## LANGUAGE EXTENSIONS

Vppreproc supports the preprocessing constructs defined in the Verilog 2001 and SystemVerilog 2005 standards.

The following additional constructs may be added to your Verilog code.

- \`\_\_FILE\_\_

  The \_\_FILE\_\_ define expands to the current filename as a string, like C++'s \_\_FILE\_\_.  This was incorporated into to the 1800-2009 standard (but supported by Verilog-Perl since 2004!)

- \`\_\_LINE\_\_

  The \_\_LINE\_\_ define expands to the current filename as a string, like C++'s \_\_LINE\_\_.  This was incorporated into to the 1800-2009 standard (but supported by Verilog-Perl since 2004!)

- \`error *string*

  This will report an error when encountered, like C++'s #error.

## DISTRIBUTION

Verilog-Perl is part of the \<https://www.veripool.org/\> free Verilog EDA software tool suite.  The latest version is available from CPAN and from \<https://www.veripool.org/verilog-perl\>.

Copyright 2000-2024 by Wilson Snyder.  This package is free software; you can redistribute it and/or modify it under the terms of either the GNU Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.

## AUTHORS

Wilson Snyder \<wsnyder@wsnyder.org\>

## SEE ALSO

Verilog-Perl, Verilog::Getopt, Verilog::Preproc