Ngspice installation instructions
=================================

Important notice: since ngspice-35 there has been an update
to the XSPICE code models (analog.cm etc.). Therefore it
is not sufficient to only re-make the main executable,
you will have to compile and install the code models as well,
e.g. with --enable-xspice.

Table of contents

  1 Ngspice installation (LINUX)
   1.1 Prerequisites
   1.2 Install from tarball (e.g. ngspice-36.tar.gz)
   1.3 Install from git repository
   1.4 ngspice as a shared library
   1.5 Advanced Install
    1.5.1 Most useful options
    1.5.2 Options Specific to Enable Ngspice as a shared library
    1.5.3 Options Useful for Debugging Ngspice
   1.6 Installation on Red Hat, Oracle or Centos Linux
  2 Compilers and Options
  3 Compiling For Multiple Architectures
  4 Installation Names
  5 Optional Features
  6 Specifying the System Type
  7 Sharing Defaults
  8 Operation Controls
  9 NGSPICE COMPILATION UNDER WINDOWS OS
   9.1 How to make ngspice with MINGW and MSYS
   9.2 make ngspice with MS Visual Studio 2019
   9.3 make ngspice with pure CYGWIN
   9.4 ngspice console app with MINGW or CYGWIN
   9.5 cross compiling ngspice for Windows from LINUX
 10 NGSPICE COMPILATION UNDER macOS
  10.1 Use precompiled binary package
  10.2 Compile NGSPICE manually from a tarball
  10.3 Compile NGSPICE manually from git
  10.4 About compilers

This file describes the procedures to install ngspice from sources.


1 Ngspice Installation (LINUX, maybe others)
  ====================

1.1 Prerequisites

 Ngspice is written in C and thus a complete C compilation environment
 is needed. Almost any LINUX offers a complete C development environment.
 Ngspice is developed on GNU/Linux with gcc and GNU make.

 Ngspice may be compiled in three different variant, each with its own
 configure settings. Standard ngsoice executable, ngspice as a shared
 library and ngspice as a tcl/tk library.

 The following software must be installed in your system to compile
 ngspice as a standard executable (command-line input, file and graphics
 output):
 bison, flex, X11 headers and libs, Xaw, Xmu, Xext, Xft, FontConfig,
 Xrender, and freetype headers (e.g. libX11-devel) and libs (e.g. libX11-6),
 and readline.

 ngspice as a shared library (no graphics and no command-line interfaces)
 will need bison and flex only.

 If libfftw is detected on your system, it will be used instead of the
 internal fft algorithms.

 If you want to compile the source from the git repository you need
 additional software: autoconf, automake, libtool.

 The following software may be needed when enabling additional features:
 editline, tcl/tk, adms.

 Please have a look at the actual ngspice manual, downloadable at
 http://ngspice.sourceforge.net/docs.html, which gives you much more
 information on ngspice and its usage.

 For compiling ngspice as a shared library, see section 1.4.


1.2 Install from tarball (e.g. ngspice-36.tar.gz)

 This covers installation from a release distribution (for example
 ngspice-36.tar.gz, the so called tar ball).

 After downloading the tar ball to a local directory unpack it using:

 $ tar -zxvf ngspice-36.tar.gz

 Now change directories in to the top-level source directory (where this
 INSTALL file can be found).

 You should be able to do:

 $ mkdir release
 $ cd release
 $ ../configure  --with-x --with-readline=yes --disable-debug
 $ make
 $ sudo make install

 The default install directory for executables is /usr/local/bin.

 A simple ../configure might be sufficient for a basic ngspice, but the preferred
 arguments to ../configure are
  --with-x --with-readline=yes and --disable-debug
 providing you with a comfortably working ngspice (see section 1.4 for details).

 See the section titled 'Advanced Install' for instructions about additional arguments
 that can be passed to ../configure to customise the build and installation.

 Do not use the script ./autogen.sh, because it is not required for
 compiling and installing ngspice from the tarball.

 A fully featured ngspice on LINUX may be obtained with the following commands:
 $ mkdir release
 $ cd release
 $ ../configure --with-x --enable-xspice --disable-debug --enable-cider --with-readline=yes --enable-openmp
 $ make 2>&1 | tee make.log
 $ sudo make install

 To remove the executables and libraries from the install directory, you may call
 $ sudo make uninstall


1.3 Install from the git repository

     This section describes how to install from source code taken directly
 from the git repository.  It is intended for those who want to use the most
 recent enhancements of ngspice and for developers. For user install
 instructions using source from a released distributions, please see the
 sections titled 'Install from tarball' and 'Advanced Install'.

 Download ngspice sources from the git repository as described on the sourceforge project page
 (see http://ngspice.sourceforge.net/download.html and click on the git link)

 Now change directories in to the top-level source directory (where this
 INSTALL file can be found).

 The project uses the GNU build process. The compile output should go into a separate
 directory, so to e.g. maintain separate debug and release versions.

 $ ./autogen.sh
 $ mkdir debug
 $ cd debug
 $ ../configure --with-x --with-readline=yes
 $ make
 $ sudo make install

 See the section titled 'Advanced Install' for instructions about arguments
 that can be passed to ./configure to customize the build and installation.

 Preferred arguments to ./configure to obtain a comfortably working ngspice may be
 --with-readline=yes and --disable-debug (for a smaller and speed optimized
 executable).

 A fully featured ngspice on LINUX may be obtained with the following commands:
 $ ./autogen.sh --adms
 $ mkdir release
 $ cd release
 $ ../configure --with-x --enable-xspice --disable-debug --enable-cider --with-readline=yes --enable-openmp --enable-adms
 $ make 2>&1 | tee make.log
 $ sudo make install

 A bash script compile_linux.sh is available including all useful options,
 compiling and installation procedures.


1.4 ngspice as a shared library

 The relevant configure options for the ngspice shared library are:
 $ --with-ngshared --enable-xspice --disable-debug --enable-cider --enable-openmp

 Typically the two aliases libngspice.so, libngspice.so.0 and the compiled
 library libngspice.so.0.0.1 are made. The install locations depend on
 the Linux distribution and may be set by the --prefix configure flag.

 Again there is a bash script compile_linux_shared.sh with all useful options,
 compiling and installation procedures.

 libtool versioning is available and may be set in configure.ac, if relevant
 changes to the source code have been made.


1.5 Advanced Install

 Some extra options can be provided to './configure'. To get all available
 options do:

 $ ./configure --help

 Some of these options are generic to the GNU build process that is used by
 Ngspice, other are specific to Ngspice.

 The following sections provide some guidance and descriptions for many,
 but not all, of these options.

 1.5.1 Most useful options:

 --enable-adms
        ADMS is an experimental model compiler that translates
        Verilog-A compact models into C code that can be compiled into
        ngspice. This is (as of ngspice-27) still experimental, some
        features (e.g. noise) are missing. If you want to use it, please
        refer to the ADMS section on ngspice web site.

 --enable-cider
        Cider is a mixed-level simulator that couples Spice3 and DSIM
        to simulate devices from their technological parameters.

 --enable-xspice
        Enable XSpice enhancements,
        A mixed signal simulator built upon spice3 with codemodel
        dynamic loading support. See the ngspice manual for details.

 --with-readline=yes
        Enable GNU readline support for the command line interface.

 --enable-openmp
        Compile ngspice for multi-core processors.
        Parallelization is done by OpenMP, for MOS models in BSIM3.3.0
        BSIM4.6.0 and and BSOI4 only. See the ngspice manual for details.

 --disable-debug
        This option will remove the '-g' option passed to the compiler
        and add -O2 optimization (instead of default O0).
        This speeds up simulating significantly, and is recommended for
        normal use.

 --enable-oldapps
        The old apllications ngsconvert ngproc2mod ngmultidec and ngmakeidx
        are made only per user request, by adding this flag.

 --with-fftw3=no
        Disable using fftw fast fourier transform library. Use internal
        fft instead. Default is 'yes'.


 --with-editline=yes
        Enables the use of the BSD editline library (libedit) instead
        of readline.
        See http://www.thrysoee.dk/editline/

1.5.2 Options Specific to Enable Ngspice as a shared library

 --with-ngshared
        This option let you compile ngspice as a shared
        library or dll, allowing an application controlling
        ngspice. This option excludes using --with-x or
        --with-wingui. Useful additional options are
        --enable-xspice --enable-cider --enable-openmp.
        No graphics interface is provided, this has to be
        handled by the controlling application.

 --with-tcl=tcldir
        When configured with this option, the tcl module
        "tclspice" is compiled and installed instead of
        plain ngspice.

1.5.3 Options Useful for Debugging Ngspice

 --enable-ansi
        Configure will try to find an option for your compiler so that
        it expects ansi-C.

--enable-asdebug
        Debug sensitivity code *ASDEBUG*.

 --enable-blktmsdebug
        Debug distortion code *BLOCKTIMES*

 --enable-checkergcc
        Option for compilation with checkergcc.

 --enable-cpdebug
        Enable ngspice shell code debug.

 --disable-debug
        This option will remove the '-g' option passed to the compiler.
        This speeds up compilation a *lot*, and is recommended for
        normal use.

 --enable-ftedebug
        Enable ngspice frontend debug.

 --enable-pzdebug
        Debug pole/zero code.

 --enable-sensdebug
                Debug sensitivity code *SENSDEBUG*.

 --enable-smltmsdebug
        Debug distortion code *SMALLTIMES*

 --enable-smoketest
        Enable smoketest compile.

 --enable-stepdebug
        Turns on debugging of convergence stepping??


 If a problem is found with the build process, please submit a report
 to the ngspice development team using the ngspice discussion forum at
 https://sourceforge.net/p/ngspice/discussion/133842/. Please provide
 information about your system and any ./configure arguments you are
 using, together with any error messages. If you have fixed the
 problem yourself, then the development team will love to hear from you.


1.6 Installation on Red Hat, Oracle or Centos

 These OSs, widely distributed among commercial users, require some
 special considerations. There is an extra document, "NGSPICE on Red
 Hat Like Distributions.pdf", provided by Justin Fisher, available with
 the ngspice distribution.


2 Compilers and Options
  =====================

     Some systems require unusual options for compilation or linking that
 the `configure' script does not know about.  You can give `configure'
 initial values for variables by setting them in the environment.  Using
 a Bourne-compatible shell, you can do that on the command line like
 this:
      CC=c89 CFLAGS=-O2 LIBS=-lposix ./configure

 Or on systems that have the `env' program, you can do it like this:
     env CPPFLAGS=-I/usr/local/include LDFLAGS=-s ./configure

 On CentOS with older GCC it might be necessary to add -std=c99
 to the CFLAGS in ./compile_linux.sh .

3 Compiling For Multiple Architectures
  ====================================

     You can compile the package for more than one kind of computer at the
 same time, by placing the object files for each architecture in their
 own directory.  To do this, you must use a version of `make' that
 supports the `VPATH' variable, such as GNU `make'.  `cd' to the
 directory where you want the object files and executables to go and run
 the `configure' script.  `configure' automatically checks for the
 source code in the directory that `configure' is in and in `..'.

     If you have to use a `make' that does not supports the `VPATH'
 variable, you have to compile the package for one architecture at a time
 in the source code directory.  After you have installed the package for
 one architecture, use `make distclean' before reconfiguring for another
 architecture.

4 Installation Names
  ==================

    By default, `make install' will install the package's files in
 `/usr/local/bin', `/usr/local/man', etc.  You can specify an
 installation prefix other than `/usr/local' by giving `configure' the
 option `--prefix=PATH'.

    You can specify separate installation prefixes for
 architecture-specific files and architecture-independent files.  If you
 give `configure' the option `--exec-prefix=PATH', the package will use
 PATH as the prefix for installing programs and libraries.
 Documentation and other data files will still use the regular prefix.

    In addition, if you use an unusual directory layout you can give
 options like `--bindir=PATH' to specify different values for particular
 kinds of files.  Run `configure --help' for a list of the directories
 you can set and what kinds of files go in them.

    If the package supports it, you can cause programs to be installed
 with an extra prefix or suffix on their names by giving `configure' the
 option `--program-prefix=PREFIX' or `--program-suffix=SUFFIX'.

 When installed on MinGW with MSYS alternative paths are not fully supported.
 See 'How to make ngspice with MINGW and MSYS' below for details.


5 Optional Features
  =================

    Some packages pay attention to `--enable-FEATURE' options to
 `configure', where FEATURE indicates an optional part of the package.
 They may also pay attention to `--with-PACKAGE' options, where PACKAGE
 is something like `gnu-as' or `x' (for the X Window System).  The
 `README' should mention any `--enable-' and `--with-' options that the
 package recognizes.

    For packages that use the X Window System, `configure' can usually
 find the X include and library files automatically, but if it doesn't,
 you can use the `configure' options `--x-includes=DIR' and
 `--x-libraries=DIR' to specify their locations.

6 Specifying the System Type
  ==========================

    There may be some features `configure' can not figure out
 automatically, but needs to determine by the type of host the package
 will run on.  Usually `configure' can figure that out, but if it prints
 a message saying it can not guess the host type, give it the
 `--host=TYPE' option.  TYPE can either be a short name for the system
 type, such as `sun4', or a canonical name with three fields:
      CPU-COMPANY-SYSTEM

     See the file `config.sub' for the possible values of each field.  If
 `config.sub' isn't included in this package, then this package doesn't
 need to know the host type.

    If you are building compiler tools for cross-compiling, you can also
 use the `--target=TYPE' option to select the type of system they will
 produce code for and the `--build=TYPE' option to select the type of
 system on which you are compiling the package.

7 Sharing Defaults
  ================

    If you want to set default values for `configure' scripts to share,
 you can create a site shell script called `config.site' that gives
 default values for variables like `CC', `cache_file', and `prefix'.
 `configure' looks for `PREFIX/share/config.site' if it exists, then
 `PREFIX/etc/config.site' if it exists.  Or, you can set the
 `CONFIG_SITE' environment variable to the location of the site script.
 A warning: not all `configure' scripts look for a site script.

8 Operation Controls
  ==================

    `configure' recognizes the following options to control how it
 operates.

 `--cache-file=FILE'
      Use and save the results of the tests in FILE instead of
      `./config.cache'.  Set FILE to `/dev/null' to disable caching, for
      debugging `configure'.

 `--help'
      Print a summary of the options to `configure', and exit.

 `--quiet'
 `--silent'
 `-q'
      Do not print messages saying which checks are being made.  To
      suppress all normal output, redirect it to `/dev/null' (any error
      messages will still be shown).

 `--srcdir=DIR'
      Look for the package's source code in directory DIR.  Usually
      `configure' can determine that directory automatically.

 `--version'
      Print the version of Autoconf used to generate the `configure'
      script, and exit.

 `configure' also accepts some other, not widely useful, options.



9 NGSPICE COMPILATION UNDER WINDOWS OS
  ====================================

9.1 How to make ngspice with MINGW and MSYS2

     Creating ngspice with MINGW is a straight forward procedure,
 if you have MSYS2/MINGW installed properly.  A modern environment is
 offered by MSYS2 (https://www.msys2.org/). An installation procedure for
 gcc in MSYS2 is decribed in
 https://github.com/orlp/dev-on-windows/wiki/Installing-GCC--&-MSYS2
 You will need some enhancements to the standard install (git, autoconf,
 automake, libtool, FLEX and BISON, all available with pacman in MSYSS2).
 Some links are given below which describe the procedures.

     Installing from the tarball, e.g. ngspice-36.tar.gz, is simple: After
 expanding, you may just run ./compile_min.sh from the ngspice directory.

     The default installation location of ngspice is the Windows path
 C:\spice. The install path can be altered by passing --prefix=NEWPATH
 as an argument to ./configure during the build process.

     Put the install path you desire inside "", e.g. "D:/NewSpice". Be
 careful to use forward slashes "/", not backward slashes "\" (something
 still to be fixed).  Then add --prefix="D:/NewSpice" as an argument to
 ./configure in the normal way.

 The procedure of compiling a distribution (for example, a tarball from
 the ngspice website), if you don't want to use the script named above
 is as follows:

 $ cd ngspice
 $ mkdir release
 $ cd release
 $ ../configure --with-wingui ...and other options
 $ make
 $ make install

 The most useful options are:
 --enable-xspice
 --enable-cider
 --disable-debug (-O2 optimization, no debug information)

 A fully featured ngspice on Windows may be obtained with the following commands:
 $ ./autogen.sh --adms
 $ mkdir release
 $ cd release
 $ ../configure --with-wingui --enable-cider --disable-debug --enable-openmp --enable-xspice --enable-adms
 $ make install

 However, to compile code extracted from the git repository the procedure is
 a little different. Firstly install git, e.g. from http://git-scm.com/download/win
 To obtain ngspice, you may do the following:

 Open the git command window. Go to a directory of your choice, e.g. D:\Spice
 $ cd /d/Spice

 Issue the command for downloading ngspice:
 $ git clone git://ngspice.git.sourceforge.net/gitroot/ngspice/ngspice

 This will create directory /ngspice .

 Go to directory ngspice
 $ cd /d/Spice/ngspice
 Start compiling, e.g. by calling
 $ ./autogen.sh --adms
 $ ./compile_min.sh

 Update the ngspice files:
 Go to directory ngspice
 $ cd /d/Spice/ngspice
 Issue command for update
 $ git pull

 Instead of calling  ./compile_min.sh, you may choose to issue
 individual commands like:
 $ cd ngspice
 $ ./autogen.sh
 $ mkdir release
 $ cd release
 $ ../configure --enable-maintainer-mode --with-wingui ...and other options
 $ make
 $ make install

 The install tree generated during 'make install' is:

  C:\Spice64\
    bin\
        ngspice.exe
        cmpp.exe
    lib\
        spice\
            analog.cm
            digital.cm
            spice2poly.cm
            extradev.cm
            extravt.cm
    share\
        man\
            man1\
                cmpp.1
                ngspice.1
        ngspice\
            scripts\
                ciderinit
                devaxis
                devload
                setplot
                spectrum
                spinit

 The scripts in directory ngspice/scripts are somewhat outdated
 (except for spinit, the basic ngspice initialization script),
 but may give some hints how to use the ngspice control language.

 A bash script compile_min.sh is available including all useful options,
 compiling and installation procedures.

 The shared library libngspice-0.dll may be created by using the
 script compile_min_shared.sh.


9.2 make ngspice with MS Visual Studio 2019

 ngspice may be compiled with MS Visual Studio 2019 or newer.

 CIDER and XSPICE are included, the code models for XSPICE
 (*.cm) are made as well.

 There is currently no installation procedure provided, you may
 however install the executable manually as described in the
 installation tree below.

 The directory (visualc) with its files
 vngspice.sln (project starter) and
 vngspice.vcproj (project contents)
 allows to compile and link ngspice with MS Visual Studio 2019.

 /visualc/include contains a dedicated config.h file. It contains the
 preprocessor definitions required to properly compile the code.
 strings.h has been necessary during setting up the project.

 Install Microsoft Visual Studio 2019 Community with C/C++. For
 example, the German edition is available at no cost from
 https://www.visualstudio.com/de/vs/community/.

 Install flex/bison from https://github.com/lexxmark/winflexbison/releases.
 When the ngspice sources are installed in D:\myspices\ngspice, then
 create a directory D:\myspices\flex-bison and expand the contents from
 https://github.com/lexxmark/winflexbison/releases/download/v2.5.24/win_flex_bison-2.5.24.zip
 into this directory.

 Goto  /ngspice/visualc.

 Start MS Visual Studio 2019 by double click onto vngspice.sln.

 After MS Visual Studio has opened up, select debug or release version
 by checking 'Build' , 'Configuration Manager', 'Debug' or 'ReleaseOmp'.
 32 bit compilation (x86) is possible, but deprecated and will be removed
 in the near future. 64 bit (x64) is the preferred option.

 Start making ngspice (called vngspice.exe) by selecting 'Build' and
 'Rebuild vngspice'.

 Object files will be created and stored in visualc/debug or visualc/release.
 The executable will be stored to visualc/debug/bin or visualc/release/bin.

 An installation tree (as provided with MINGW make install) and also used by
 vngspice is (maybe created manually):

 C:\Spice64\
    bin\
        ngspice.exe
    lib\
        spice\
            analog.cm
            digital.cm
            spice2poly.cm
            extradev.cm
            extravt.cm
    share\
        ngspice\
            scripts\
                spinit

 If you intend to install vngspice into another directory, e.g. D:\MySpice,
 you have to edit  /visualc/include/config.h and alter the entries:
 #define NGSPICEBINDIR "C:/Spice64/bin"
 #define NGSPICEDATADIR "C:/Spice64/share/ngspice"
 to
 #define NGSPICEBINDIR "D:/MySpice/bin"
 #define NGSPICEDATADIR "D:/MySpice/share/ngspice"

 If the code model files *.cm are not available, you will get warning messages,
 but you may use ngspice in the normal way (of course without XSPICE extensions).

 The ngspice.dll shared library may be made by selecting sharedspice.sln from
 ngspice/visualc. Code models are not made (see above how to generate them), and
 ngspice.dll is not installed to anywhere, but (for release) may be found in
 ngspice\visualc\sharedspice\ReleaseOMP.x64.



9.3 make ngspice with pure CYGWIN

 If you don't have libdl.a you may need to link libcygwin.a
 to libdl.a symbolically.

 for example:

 $ cd /lib
 $ ln -s libcygwin.a libdl.a.

 The procedure of compiling is the same as Linux.


9.4 ngspice console app with MINGW or CYGWIN

 Omitting the configure flag --with-wingui will yield a console ngspice.
 You then will not have any graphics interface. In CYGWIN you may add --with-x
 for the X11 graphics (not available in mingw). A typical configure command
 may look like
 ./configure --enable-adms --enable-xspice --enable-cider --enable-openmp
 --disable-debug CFLAGS=-m64 LDFLAGS=-m64 prefix=C:/Spice64


9.5 cross compiling ngspice for Windows from LINUX

Two scripts are available in the ngspice directory that allow cross
compiling for NMS Windows, if you are running LINUX. ngspice.exe or
ngspice.dll may be made. For details please see cross-compile.sh or
cross-compile-shared.sh.


10 NGSPICE COMPILATION UNDER macOS
   ==================================

10.1 Use precompiled binary package
 1. Install an X11 interface (like Xquartz)
 2. Packages are available from Homebrew or MacPorts
    Install the downloaded NGSPICE package
    It may happen though that a package has been compiled without graphics support
 3. Open a terminal window and start using NGSPICE

10.2 Compile NGSPICE manually from a tarball
 1. Install an X11 interface (like Xquartz)
 2. Install MacPorts from http://www.macports.org
 3. Execute this command:
      sudo port install autoconf automake libtool bison flex ncurses
           readline fontconfig freetype libomp xorg-libXaw
 4. Use one of the scripts provided: compile_macos.sh or build-for-mac-os.sh
 5. Or run the commands manually:  Configure NGSPICE invoking "./configure".
    A complete set of features is:
      ./configure --enable-cider --enable-xspice --enable-openmp --enable-pss --enable-debug=no
 6. Compile NGSPICE invoking "make -j4"
 7. Install NGSPICE invoking "make install" or "sudo make install"

10.3 Compile NGSPICE manually from git
 1. Install an X11 interface (like Xquartz)
 2. Install MacPorts from http://www.macports.org
 3. Execute this command:
      sudo port install automake autoconf libtool bison flex ncurses xorg-libXaw
          readline fontconfig freetype libomp SM ICE
 4. Execute this command:
      ./autogen.sh or ./autogen.sh --adms (if you want to enable ADMS)
 5. Configure NGSPICE invoking "./configure". A complete set of feature is:
      ./configure --enable-cider --enable-xspice --enable-openmp --enable-pss --with-readline=yes --enable-debug=no
      or (if you want to enable ADMS)
      ./configure --enable-adms --enable-cider --enable-xspice --enable-openmp --enable-pss --with-readline=yes --enable-debug=no
 6. Compile NGSPICE invoking "make -j4"
 7. Install NGSPICE invoking "make install" or "sudo make install"

Resulting dependencies of ngspice
    /usr/local/opt/ncurses/lib/libncursesw.6.dylib
    /usr/local/opt/gcc/lib/gcc/11/libstdc++.6.dylib
    /usr/local/opt/fftw/lib/fftw3.3.dylib
    /usr/local/opt/readline/lib/libreadline.8.dylib
    /opt/local/lib/libXaw.7.dylib
    /opt/local/lib/libXmu.6.dylib
    /opt/local/lib/libXt.6.dylib
    /opt/local/lib/libXext.6.dylib
    /opt/local/lib/libX11.6.dylib
    /opt/local/lib/libfontconfig.1.dylib
    /opt/local/lib/libXrender.1.dylib
    /opt/local/lib/libfreetype.6.dylib
    /opt/local/lib/libSM.6.dylib
    /opt/local/lib/libICE.6.dylib
    /usr/local/opt/gcc/lib/gcc/11/libgomp.1.dylib
    /usr/lib/libSystem.B.dylib
    /usr/local/lib/gcc/11/libgcc_s.1.dylib

 10.5 About compilers
    A compile script compile_macos_clang.sh contains all necessary steps for compiling
    with the Xcode clang/llvm compiler. This compiler however does not support -fopenmp.
    Therefore you may download and install gcc, e.g. from Homebrew and run the new
    compile script compile_macos_gcc.sh. OpenMp enables parallel processing of
    BSIM3/4 model evaluation, thus speeding up simulation.

