Arm Compiler 6 Downloads

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Downloads

Version 6.5

Released: June 30, 2016

Windows 64-bit
File: DS500-BN-00024-r5p0-06rel0.zip (118.97 MB)
Windows 32-bit
File: DS500-BN-00025-r5p0-06rel0.zip (112.35 MB)
Linux 64-bit
File: DS500-BN-00026-r5p0-06rel0.tgz (174.67 MB)

Release Note for Arm Compiler 6 Downloads 6.5

ARM Logo

Release notes for ARM Compiler 6.5

1. Introduction

ARM Compiler 6.5 adds:

  • Support for Cortex-A73.

The compiler also includes a number of optimizations that result in better performance of the generated code over the previous release, and some improvements in code size.

ARM Compiler 6.5 is intended for use:

  • In conjunction with DS-5 Professional Edition or DS-5 Ultimate Edition to build and debug executable code for the supported architectures.
  • As a standalone toolchain installation.

A suitable license from one of these products must be available. Contact your sales representative or visit https://developer.arm.com/products/buy-arm-products to enquire about a license.

If you are using a floating license, your license server must be running armlmd and lmgrd version 11.12.1.0 or later. In November 2015, Flexera published notification of security vulnerabilities that were discovered in the lmgrd and vendor daemon components of FlexNet Publisher. Flexera have no reason to believe that the vulnerabilities have been exploited but nevertheless provided a security update in version 11.13.1.2. ARM recommends that you always use the latest version of the license server software that is available from https://developer.arm.com/products/software-development-tools/license-management/downloads.

1.1 ARM Compiler 6 Configuration

ARM Compiler 6 is the successor to ARM Compiler 5 and includes the components listed below. See the Migration and Compatibility Guide in the product documentation for more information on migrating projects from previous versions.

  • armclang
    • armclang is the successor to armcc and is based on LLVM technology.
  • armlink, armasm, fromelf, armar
    • armlink, armasm, fromelf, and armar have been extended to support ARMv8 and behave similarly to ARM Compiler 5.
  • ARM C and C++ libraries for embedded systems
    • The standard ARM Compiler embedded libraries have been extended to support ARMv8 and behave similarly to those found in ARM Compiler 5, although they might not be fully feature complete.
    • ARM Compiler 6 includes the libc++ library as the C++ Standard Template Library.

Note regarding assemblers:

  • ARM Compiler 6 adopts the LLVM integrated assembler as default because it aligns more closely with GNU assembler syntax, improving portability between GNU and ARM Compiler toolchains. The LLVM integrated assembler is called by default by armclang. A side effect is that ARM Compiler 6 will not compile C/C++ source files which contain legacy armcc inline or embedded assembler.
  • Although armasm is not called by default, it is included in ARM Compiler 6 for assembling assembler files written in legacy armasm syntax.

1.2 What's Supported in ARM Compiler 6.5?

Architecture and Processors Support Level
ARMv8.2-A, ARMv8.1-A, ARMv8-A and ARMv7-A and derived processors Product feature.
ARMv8-R, ARMv7-R and derived processors Product feature.
ARMv8-M, ARMv7-M, ARMv6-M and derived processors Product feature.
ARM Architectures earlier than ARMv6-M Unsupported. Please use ARM Compiler 5.
Non ARM architectures Unsupported.
Support Level Description
Product features Production quality. Highest support priority.
Beta product features Implementation complete, but not thoroughly tested. User experimentation and feedback is welcomed.
Alpha product features Implementation is not complete and not thoroughly tested. User experimentation and feedback is welcomed.
Community features Additional features that are available in the open-source technology ARM Compiler 6 is built on. ARM makes no claims about the quality level or the degree of functionality of these features. User experimentation and feedback is welcomed.
Unsupported features Features that are either not present in the toolchain or have been deprecated. These features are completely untested. Use entirely at your own risk.

For more information on the supported features and level of support for features, see the product documentation.

2. Installation Instructions

If you received ARM Compiler 6.5 as part of a toolkit, for example DS-5, the toolkit installer takes care of the installation process. Please refer to the installation instructions for the toolkit in such cases.

For all other cases, you must select an appropriate installation location depending on how you intend to use ARM Compiler 6.5:

  • Integrated into DS-5 5.20 or later.
  • As a standalone product.

2.1. Integration into DS-5 5.20 or later

ARM Compiler 6.5 can be installed in any location, including the default location, providing this is outside of a DS-5 product installation.

After it is installed, you can integrate the toolchain with DS-5 5.20 or later by following the instructions in the tutorial available at https://developer.arm.com/products/software-development-tools/ds-5-development-studio/resources/tutorials/adding-new-compiler-toolchains-to-ds-5.

ARM recommends using ARM Compiler 6.5 from the DS-5 Eclipse IDE or DS-5 Command Prompt. When using the toolchain outside these environments, you might need to configure the following environment variables:

  • Set ARM_PRODUCT_PATH to the path to the sw/mappings directory within your DS-5 installation.
  • Set ARM_TOOL_VARIANT=ult if you are using the toolchain with DS-5 Ultimate Edition.

2.2. Use as a standalone product

ARM Compiler 6.5 can be installed in any location, including the default location, providing this is outside of a DS-5 product installation.

Ensure that the ARMLMD_LICENSE_FILE environment variable is pointing to your license file or license server. Please note this path must not contain double quotes on Windows. A path that contains spaces will still work without the quotes.

Set ARM_TOOL_VARIANT=ult if you are using the toolchain with a DS-5 Ultimate Edition license.

2.3. Installation on Linux

ARM Compiler 6.5 has been tested on the following supported platforms:

  • Red Hat Enterprise Linux 6 Workstation, 64-bit only.
  • Red Hat Enterprise Linux 7 Workstation, 64-bit only.
  • Ubuntu Desktop Edition 14.04 LTS, 64-bit only.

ARM Compiler 6.5 is not expected to work on older platforms.

To install ARM Compiler 6.5, run (not source) install_x86_64.sh and follow the on-screen instructions. The installer unpacks ARM Compiler 6.5 into your chosen directory.

The armclang binary is dynamically linked to a copy of libstdc++ installed under your chosen directory as part of ARM Compiler 6.5.

Some of the installed tools have dependencies on 32-bit system libraries. You must ensure that 32-bit compatibility libraries are installed when using ARM Compiler 6.5 on 64-bit Linux host platforms. ARM Compiler 6.5 tools might fail to run or report errors about missing libraries if 32-bit compatibility libraries are not installed. To install the required libraries, run the appropriate command for your platform with root privileges:

Red Hat
yum install glibc.i686
Ubuntu
apt-get install lib32stdc++6

2.4. Installation on Windows

ARM Compiler 6.5 has been tested on the following supported platforms:

  • Windows Server 2012, 64-bit only.
  • Windows 7 Enterprise SP1.
  • Windows 7 Professional SP1.
  • Windows 8.1 Enterprise, 64-bit only.
  • Windows 8.1 Professional, 64-bit only.
  • Windows 10 Enterprise, 64-bit only.
  • Windows 10 Professional, 64-bit only.

ARM Compiler 6.5 is not expected to work on older platforms.

To install ARM Compiler 6.5, run win-x86_64\setup.exe on a 64-bit Windows host platform or win-x86_32\setup.exe on a 32-bit Windows host platform and follow the on-screen instructions. If you have an earlier version of ARM Compiler 6 installed and you wish to perform an upgrade, it is recommended that you uninstall the previous version before installing the new version of ARM Compiler 6.

ARM Compiler 6 requires the Microsoft Visual Studio 2013 runtime libraries to be installed. If you use the product installer, or the toolchain is installed as part of DS-5, the runtime libraries are installed with the product. If you later copy or move the installation to another host you will need to ensure that the runtime libraries are also available on that host.

3. Uninstall

On Linux, delete the ARM Compiler 6.5 installation directory.

On Windows, use Programs and Features in Control Panel, select ARM Compiler 6.5, and click the Uninstall button.

4. Documentation

The following documentation is available for ARM Compiler 6.5:

  • armar User Guide.
  • armasm User Guide.
  • armclang Reference Guide.
  • armlink User Guide.
  • fromelf User Guide.
  • ARM C and C++ Libraries and Floating-Point Support User Guide.
  • Migration and Compatibility Guide.
  • Getting Started Guide.
  • Software Development Guide.
  • Errors and Warnings Reference Guide.

For more information, please see ARM Compiler 6 documentation in developer.arm.com.

5. Feedback and Support

Your feedback is important to us, and you are welcome to send us defect reports and suggestions for improvement on any aspect of the product. Contact your supplier or visit https://developer.arm.com/support and open a case with feedback or support issues. Where appropriate, please provide the --vsn output from the tool, the complete content of any error message that the tools produce, and include any source code, other files, and command-lines necessary to reproduce the issue.

6. Release History and Changes

The following are the releases to date of the ARM Compiler 6.5 series:

  • 6.5 (released June 2016)

Below is a summary of the changes in each release, including new features and defect fixes. Changes are listed since the previous release in each case unless otherwise specified. Each itemized change is accompanied by a unique SDCOMP-<NNNNN> identifier. If you need to contact ARM about a specific issue within these release notes, please quote the appropriate identifier.

Changes in ARM Compiler 6.5

Changes are listed since the previous feature release, ARM Compiler 6.4.

General changes in ARM Compiler 6.5

  • [SDCOMP-27650]  Support has been added for the following intrinsics:

    • __breakpoint
    • __current_pc
    • __disable_fiq
    • __disable_irq
    • __enable_fiq
    • __enable_irq
    • __force_stores
    • __memory_changed
    • __schedule_barrier
    • __semihost
    • __vfp_status

    These intrinsics are defined in the header file arm_compat.h.

  • [SDCOMP-30327]  The Read-Only Position-Independent (ROPI) and Read/Write Position-Independent (RWPI) code features are now fully supported. Position independent applications can be built with the following options:

    armclang:

    • -fropi to enable the generation of ROPI code.
    • -frwpi to enable the generation of RWPI code.

    armlink:

    • --ropi to make the load and execution region containing the RO output section position-independent.
    • --rwpi to make the load and execution region containing the RW and ZI output section position-independent.

    For more information about these options, refer to the armclang Reference Guide and the armlink User Guide.

  • [SDCOMP-30644]  Support for the ARMv8 RAS Extension has been added to the compiler. To target systems with the RAS Extension, select from the following options:

    • -march=armv8-a+ras
    • -march=armv8.1-a+ras
    • -march=armv8.2-a
    • -march=armv8-r+ras

  • [SDCOMP-44590]  The ARMv8.2-A FP16 half-precision floating-point (FP16) and Statistical Profiling (SPE) extensions are now fully supported. To target these optional features, select from the following options:

    Architecture armclang armasm, armlink, and fromelf
    ARMv8.2-A AArch64 with FP16 and SPE -march=armv8.2-a+fp16+profile --cpu=8.2-A.64 (optional --fpu=FP-ARMv8_FP16)
    ARMv8.2-A AArch64 with FP16, no SPE -march=armv8.2-a+fp16 No equivalent - SPE is always enabled
    ARMv8.2-A AArch64 no FP16, with SPE -march=armv8.2-a+profile --cpu=8.2-A.64 --fpu=FP-ARMv8
    ARMv8.2-A AArch64 no FP16 or SPE -march=armv8.2-a (optional -march=armv8.2-a+nofp16+noprofile) No equivalent - SPE is always enabled
    ARMv8.2-A AArch32 with FP16 -march=armv8.2-a+fp16 --cpu=8.2-A.32
    --fpu=FP-ARMv8_FP16
    ARMv8.2-A AArch32 no FP16 -march=armv8.2-a+nofp16 --cpu=8.2-A.32 (optional --fpu=FP-ARMv8)

    For more information about these options, refer to the product documentation.

  • [SDCOMP-45021]  Support has been added for the Cortex-A73 processor. To target Cortex-A73, select from the following options:

    armclang:

    • --target=aarch64-arm-none-eabi -mcpu=cortex-a73 for AArch64 state.
    • --target=arm-arm-none-eabi -mcpu=cortex-a73 for AArch32 state.

    armasm, armlink, and fromelf:

    • --cpu=8-A.64 for AArch64 state.
    • --cpu=8-A.32 for AArch32 state.

  • [SDCOMP-48519]  The @file option allows additional command-line options to be specified to the compiler using a file, also known as a response file or via file. The format of these files has been changed to avoid ambiguities in identifying the separate options contained in the file. All spaces and special characters within an option, including backslashes in Windows-style file paths, must now be escaped by preceding them with a backslash character. For example, a response file that contains:

    -IC:\my work\project1 -IC:\my work\project1\include
    

    must be changed to:

    -IC:\\my\ work\\project1 -IC:\\my\ work\\project1\\include
    

Enhancements in ARM Compiler 6.5

Compiler and integrated assembler (armclang)
  • [SDCOMP-45161]  Support has been added for a new maximum optimization level:

    • -Omax

    This option specifically targets performance by enabling all the optimizations from -Ofast together with other aggressive optimizations. This option is not guaranteed to be fully standards-compliant for all cases.

    For more information, refer to the armclang Reference Guide.

  • [SDCOMP-44921]  Support has been added for the following options which can be used to configure certain behaviors of the compiler:

    • -fno-strict-aliasing to disable strict aliasing rules when compiling at -O1 or above.
    • -ftrapv to generate traps for signed arithmetic overflow on addition, subtraction, and multiplication operations.
    • -fwrapv to instruct the compiler to assume that signed arithmetic overflow of addition, subtraction, and multiplication wraps using two’s complement representation.

    For more information about these options, refer to the armclang Reference Guide.

  • [SDCOMP-44901]  Support has been added for __attribute__((value_in_regs)). This function attribute alters the calling convention of a function so that the returned structure is stored in the argument registers rather than being written to memory using an implicit pointer argument.

Linker (armlink)
  • [SDCOMP-45250]  The linker previously selected --legacyalign by default. This behavior has been changed. The linker now selects --no_legacyalign by default.

Libraries and system headers
  • [SDCOMP-30143]  Beta support has been added for a variant of the standard C++ library that does not use C++ exceptions. The linker will select this variant of the library when code has been compiled with -fno-exceptions.

Defect fixes in ARM Compiler 6.5

Compiler and integrated assembler (armclang)
  • [SDCOMP-45084]  When using the ACLE __arm_wsr intrinsic within an if statement to write to one of the xPSR registers, the compiler could incorrectly emit an MSR instruction within an IT block that changes the condition flags required by later instructions in the same IT block. This has been fixed.

  • [SDCOMP-44891]  When assembling code containing a .cpu directive after a .thumb directive, the integrated assembler would generate a Thumb section that incorrectly contained ARM instructions. This could result in both incorrect behavior and incorrect disassembly output. This has been fixed.

  • [SDCOMP-44570]  In rare circumstances, when compiling at any optimization level except -O0 for AArch64, the compiler could generate incorrect code for a comparison to zero. This has been fixed.

  • [SDCOMP-32881]  In rare circumstances, when compiling for Thumb state, the compiler could generate incorrect code for a comparison when all of the following are true:

    • The comparison involves integers of different sizes.
    • The result is used for a purpose other than branching. For example, the result is passed into a function or saved into another variable.

    This has been fixed.

  • [SDCOMP-30487]  When assembling a directive of the form .eabi_attribute tag, name where tag is a valid textual Tag_ name, the inline assembler and integrated assembler would incorrectly report error: attribute name not recognised on a Windows host platform. This has been fixed.

Legacy assembler (armasm)
  • [SDCOMP-45271]  When assembling VMRS or VMSR instructions for an ARMv7E-M or ARMv8-M target with the Floating-point Extension, the assembler would incorrectly accept system registers other than FPSCR. This has been fixed. The assembler now reports Error: A1477E: This register combination results in UNPREDICTABLE behaviour.

Linker (armlink)
  • [SDCOMP-45348]  In rare circumstances, when linking AArch64 objects that support C++ exceptions, which also contain undefined and unused global symbols, the linker could report Internal fault: [0x3667ac:<ver>]. This has been fixed.

  • [SDCOMP-45197]  When linking with --import_cmse_lib_out, the linker would generate objects that incorrectly did not have the ARM ABI Version tag set. This has been fixed.

Libraries and system headers
  • [SDCOMP-45269]  The microlib implementation of the fclose() function selected by asm(".global __use_full_stdio\n"); would incorrectly fail to free the memory allocated for the FILE structure by fopen(). This could result in a memory leak. This has been fixed.

  • [SDCOMP-44778]  The standard headers contained legacy ARM Compiler 5 __declspec attributes that are not recognized by the compiler. This has been fixed. All __declspec attributes in the standard headers have been replaced by equivalent __attribute__ specifiers.

  • [SDCOMP-32959]  In rare circumstances, printing a long double value using the microlib implementation of the printf() function could result in an infinite loop. This has been fixed.

  • [SDCOMP-30944]  The microlib implementations of the snprintf() and vsnprintf() functions would incorrectly attempt to write to their output pointer when passed a length of zero. This has been fixed.

Known issues in ARM Compiler 6.5

  • [SDCOMP-45533]  In certain circumstances, when linking code that uses __attribute__((weak)) to weakly reference a variable or a function, the linker can incorrectly report Error: L6769E: Relocation #RELA:2 in <objectname.o>(.text) with respect to <referenced symbol>. No GOTSLOT exists for symbol.

  • [SDCOMP-45479]  In certain circumstances, when compiling with -fropi or -frwpi, the compiler incorrectly fails to generate initialization code for global variables that depend on the address of position-independent data or code when the initialization expression contains parentheses. This results in the linker reporting Error: L6248E: <objname>(<secname>) in <attr1> region '<r1>' cannot have <rtype> relocation to <symname> in <attr2> region '<r2>'. A workaround for this issue is to remove the parentheses.

  • [SDCOMP-30540]  In certain circumstances, when linking C++ objects that have been compiled for an AArch64 target, the linker can incorrectly report Warning: L6806W: Relocation #RELA:<index> in <object1>(<section1>) with respect to [Anonymous Symbol]. Branch to untyped symbol in <object1>(<section2>), ABI requires external code symbols to be of type STT_FUNC. This warning can be ignored if <section2> is within the range of a BL instruction from <section1>.

  • [SDCOMP-28016]  long double is not supported for AArch64 state.

  • [SDCOMP-26080]  Complex numbers are not supported.

  • [SDCOMP-25307]  When linking using the --cpu=cortex-a5 option, the linker can report Error: L6366E: <object> attributes are not compatible with the provided cpu and fpu attributes. Compiling with the --target=armv7-arm-none-eabi -mcpu=cortex-a5 options generates objects for a CPU with VFPv4 and NEON, whereas the linker option --cpu=cortex-a5 assumes a CPU without VFP and NEON. A workaround for this issue is to link using --cpu=cortex-a5.neon.