Build instructions


These instructions are outdated. Use the Building NSS page for more recent information.

Numerous optional features of NSS builds are controlled through make variables.

gmake is GNU make, usually your Linux-distro-regular “make” binary file, unless maybe it is a BSD make. Make variables may be set on the gmake command line, e.g.,

gmake variable=value variable=value target1 target2

or defined in the environment, e.g. (for POSIX shells),

variable=value; export variable
gmake target1 target2

Here are some (not all) of the make variables that affect NSS builds:

  • BUILD_OPT: If set to 1, means do optimized non-DEBUG build. Default is DEBUG, non-optimized build.

  • USE_DEBUG_RTL: If set to 1, on Windows, causes build with debug version of the C run-time library.

  • NS_USE_GCC: On platforms where gcc is not the native compiler, tells NSS to build with gcc instead of the native compiler. Default is to build with the native compiler.

  • USE_64: On platforms that support both 32-bit and 64-bit ABIs, tells NSS to build for the 64-bit ABI. Default is 32-bit ABI, except on platforms that do not support a 32-bit ABI.

  • MOZ_DEBUG_SYMBOLS: tells NSS to build with debug symbols, even in an optimized build. On windows, in both DEBUG and optimized builds, when using MSVC, tells NSS to put symbols in a .pdb file. Required to build with MSVC 8 (2005 Express). Default is not to put debug symbols into optimized builds, and for MSVC, is to put symbols into the .exe or .dll file.

  • NSDISTMODE: If set to ‘copy’, mozilla/dist/<OBJ_STUFF>/bin/* real files instead of symbolic links.

These variables should be either undefined, or set to “1”. Results are undefined for variables set to “0”.

For Windows, install the MozillaBuild environment and Microsoft Visual Studio 2010. (The free edition works, and other versions like Visual Studio 2008 and Visual Studio 2012 may also work.) Use start-shell-msvc2010.bat from MozillaBuild to get a bash shell with the PATH already configured, and execute these instructions from within that bash shell.

For RHEL-5, you need to use the new assembler. You can install the new assembler as root as follows:

yum install binutils220

You can then use the new assembler by adding /usr/libexec/binutils220 to the beginning of your build path. This can be done in sh or bash as follows:

export PATH=/usr/libexec/binutils220:$PATH

The following build instructions should work for all platforms (with some platform-specific changes as noted).

Build Instructions for Recent Versions (Mercurial)

  1. Clone the NSPR and NSS repositories.

    hg clone
    hg clone
  2. If you want to build a releases other than the tips of these repositories, then switch to the release tags:

    cd nspr
    hg update NSPR_4_9_5_RTM
    cd ../nss
    hg update NSS_3_14_2_RTM
    cd ..
  3. Set environment variables:

    1. If you want a non-debug optimized build, set BUILD_OPT=1 in your environment. Otherwise, you get a debug build. On Windows, if you want a debug build with the system’s debug RTL libraries, set USE_DEBUG_RTL=1 in your environment.

    2. On Unix platforms, except Alpha/OSF1, if you want a build for the system’s 64-bit ABI, set USE_64=1 in your environment. By default, NSS builds for the 32-bit environment on all platforms except Alpha/OSF1.

    3. To build with gcc on platforms other than Linux and Windows, you need to set two more environment variables:


    4. For HP-UX, you must set the environment variable USE_PTHREADS to 1.

  4. cd nss

  5. gmake nss_build_all

The output of the build will be in the dist directory alongside the nspr and nss directories.

For information on troubleshooting the build system, see troubleshoot.

Build Instructions for Older Versions (CVS)

  1. Set the environment variable CVSROOT to

  2. cvs login (if you haven’t before).

  3. Check out NSPR and NSS:

    cvs co -r NSPR_4_9_5_RTM NSPR
    cvs co -r NSS_3_14_2_RTM NSS
  4. Set environment variables as described in the Mercurial-based instructions.

  5. cd mozilla/security/nss

  6. gmake nss_build_all

The output of the build will be in mozilla/dist subdirectory.

For information on troubleshooting the build system, see troubleshoot.