GCC: Using a GNU GCC Compiler Toolchain in the IDE

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Information in this article applies to:

• GNU C Compiler for Arm, all versions
• µVision 3.21, and later

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QUESTION

Does the µVision IDE support the GNU toolchain? Is there a way to select a different version of a GNU ARM toolchain? What are the steps required?

When I try to translate with the some GNU toolchains I get the following error messages:

--- Error: can't execute 'as'
--- Error: can't execute 'gcc'

What causes this error?

ANSWER

There have been many different variants of the GCC compiler for ARM devices. Modern versions of Keil still support the GCC compiler, but now uses the GNU Arm Embedded Toolchain. To use this toolchain with Keil, do the following.

1. Download the GNU Arm Embedded Toolchain from the Arm Developer website.
2. Follow these steps to configure a Keil Project to use the GNU Arm Embedded Toolchain.
3. To debug a project that uses the GCC toolchain, there is an extra step needed. See µVision DEBUGGER: SOURCE LEVEL DEBUGGING WITH GNU ARM.

Note: As an alternative to use the GCC toolchain, the Arm Compilers support some GCC extensions, and have comparability with GCC.

• For the modern Arm compiler toolchain, see GCC compatibility provided by Arm Compiler 6
• For the ARMCC compiler toolchain see GNU extensions to the C and C++ languages

ANSWER FOR µVISION VERSIONS 3.21 to 4.00

To use GNU toolchain variants, µVision V3.21 allows you to specify a GNU-Tool-Prefix. If this parameter is not configured properly, you may get the error message shown above.

To select the GNU toolchain open the dialog Project - Components, Environment, Books - Folders/Extensions.

Use GNU Tools selects the GNU development tools for a project. The setting Cygnus Folder specifies the path to the GNU installation folder. The GNU-Tool-Prefix allows you to use GNU toolchain variants.

Examples for the various GNU versions:

GNU V3.22 with uclib:

• GNU-Tool-Prefix: arm-uclibc-
• Cygnus Folder: C:\Cygnus

CodeSourcery G++ with new-lib:

• GNU-Tool-Prefix: arm-none-eabi-
• Cygnus Folder: C:\Program Files\CodeSourcery\Sourcery G++\

GNUARM V4 with standard library:

• GNU-Tool-Prefix: arm-elf-
• Cygnus Folder: C:\Program Files\GNUARM\

MORE INFORMATION

• Getting Started User's Guide for Arm, Development Tools, select the Toolset
• Refer to GNU C Compiler Support in the µVision User's Guide.
• µVision DEBUGGER: SOURCE LEVEL DEBUGGING WITH GNU ARM

SEE ALSO

• ARM: Target Not Created - Can't Execute Message
• Refer to GCC compatibility provided by Arm Compiler 6 in the Compiler Getting Started Guide.
• Refer to GNU extensions to the C and C++ languages in the Compiler User Guide.

Last Reviewed: Friday, February 5, 2021

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