Flang Binary Release 2018-12-26

Flang is a Fortran compiler targeting LLVM.

The source is at http://github.com/flang-compiler/. There are 3 repositories:

• llvm: The version of LLVM that we use to build Flang.
• flang-driver: A Clang fork used as the basis of the Flang driver.
• flang: The Flang compiler itself.

This binary release was created from the flang_20181226 tag of Flang. It contains the binaries and libraries suitable for running Flang (LLVM 6.0) on x86_64 and OpenPOWER distributions.

Community Resources

We have mailing lists for announcements and developers. Here's the link with the sign-up information:

http://lists.flang-compiler.org/mailman/listinfo

We have a flang-compiler channel on Slack. Slack is invitation only but anyone can join. Here's the link:

https://join.slack.com/t/flang-compiler/shared_invite/MjExOTEyMzQ3MjIxLTE0OTk4NzQyNzUtODQzZWEyMjkwYw

Installing

To install the binary release, untar the .tgz file in a location suitable for you. Add the bin directory to your PATH and lib directory to your LD_LIBRARY_PATH, after which you should be able to execute Flang.

Building Your First Program

To test your installation, create a simple "hello world" program, like the following:

   program hello
     print *, 'hello world'
   end

Next, compile the program in the following manner. We will assume the program is in a file called hello.f90

$ flang hello.f90

If the build succeeds, then you can execute the program:

$ ./a.out

Flang Binary Release Minimum Requirements

Below are the minimum requirements to compile and run Flang:

Host Processor:
    64-bit OpenPOWER
    64-bit x86 (including AMD64 and Intel 64)

OpenPOWER Linux:
    Ubuntu 14.04, 16.04
    Red Hat Enterprise Linux 7.3, 7.4 for IBM Power (POWER8)
    Red Hat Enterprise Linux 7.4 for IBM Power LE (POWER9)

x86-64 Linux:
    CentOS 5 or newer
    OpenSuSE 11 or newer including OpenSuSE Leap 42.2
    SUSE Linux Enterprise Server (SLES) 11 or newer
    Red Hat Enterprise Linux 5 or newer
    Fedora Core 6 or newer
    Ubuntu 12.04 or newer

Flang Binary Release File List

Below is a list of files in the tar archives for x86-64 and OpenPOWER:

bin/clang
bin/clang-6.0
bin/clang++
bin/flang
bin/flang1
bin/flang2
include/ieee_arithmetic_la.mod
include/ieee_arithmetic.mod
include/ieee_exceptions_la.mod
include/ieee_exceptions.mod
include/ieee_features.mod
include/iso_c_binding.mod
include/iso_fortran_env.mod
include/omp_lib.h
include/omp_lib_kinds.mod
include/omp_lib.mod
lib/libflang.a
lib/libflang.so
lib/libflangmain.a
lib/libflangrti.a
lib/libflangrti.so
lib/libomp.a
lib/libomp.so
lib/libompstub.a
lib/libompstub.so
lib/libpgmath.a
lib/libpgmath.so

Compiler Options

For a list of compiler options, enter

$ flang -help

The Flang compiler supports all clang 6.0 compiler options as well as the following Flang-specific compiler options:

| Option | Description | | :----- | :---------- | | -byteswapio | Swap byte-order for unformatted input/output | | -cpp | Preprocess Fortran files | | -fbackslash | Treat backslash as C-style escape character | | -fdefault-integer-8 | Treat INTEGER and LOGICAL as INTEGER*8 and LOGICAL*8 | | -fdefault-real-8 | Treat REAL as REAL*8 | | -ffixed-form | Enable fixed-form format for Fortran | | -ffixed-line-length-value | Set line length in fixed-form format Fortran, current supporting only 72 and 132 characters | | -ffree-form | Enable free-form format for Fortran | | -fno-backslash | Treat backslash like any other character in character strings | | -fno-fixed-form | Disable fixed-form format for Fortran | | -fno-fortran-main | Don't link in Fortran main | | -fno-free-form | Disable free-form format for Fortran | | -Mallocatable=value | Select semantics for assignments to allocatables (F03 or F95) | | -Minfo | Diagnostic information about all successful optimizations | | -Minform=value | Set error level of messages to display | | -Minfo=value | Diagnostic information about successful optimizations | | -Mneginfo | Diagnostic information about all missed optimizations | | -Mneginfo=value | Diagnostic information about missed optimizations | | -nocpp | Don't preprocess Fortran files | | -no-flang-libs | Do not link against Flang libraries | | -static-flang-libs | Link using static Flang libraries |

Known Issues

See the GitHub issues list for the known issues with Flang: http://github.com/flang-compiler/flang/issues

The following "check-flang" tests fail on OpenPOWER:

f90_correct/daz.f90
f90_correct/lit/ieee18flushz.sh
f90_correct/lit/ieee19flushz.sh