The Renesas H8 C/C++ Compiler is an optimizing ANSI C and ANSI C++ compiler for H8, H8S, H8SX family microcontrollers. The package includes a compiler, assembler, linker. A variety of optimization features allow you to generate highly optimized PROMable code. In particular, code can be optimized for size or speed to match the requirements of the particular application being developed. The compiler toolchain is supplied as part of the High-performance Embedded Workshop IDE.

HEW, a powerful yet easy to use tool suite, features an industry standard user interface and is designed using a modular approach seamlessly incorporating device family-specific C/C++ compilers and the debugger elements for various debugging platforms including emulators and evaluation boards.


  • High-performance Embedded Workshop [Learn More]
  • Tool chain
  • C/C++ Compiler
    • Exception handling and Template functions are supported according to ANSI/ISO standards.
    • Optimizing function
    • Embedded function
  • Assembler
    • Pre-processor function
  • Optimizing Linkage Editor
    • Optimizing function
    • Output file
  • Standard Library Generator
  • Format Converter
  • Simulator [Learn More]
  • Call Walker
  • Map Viewer
  • Learn More

Release Information

Latest Ver.: V.7.00 Release00

Released: Sep 1, 2009

Details of upgrade (See Tool News)

Operating Environment

Standard life cycle of Compilers (PDF | English, 日本語)


  • V.6.02 Release 02 is the latest version in Ver.6.
  • When you run MISRA C Rule Checker SQMlint in combination with the C/C++ Compiler Package for H8SX, H8S, H8 Family V.7.00 or later, use SQMlint V.1.03 Release 00A or later.

Target Devices



Design & Development

Sample Code

Additional Details


[C/C++ Compiler]

  • Generation of Object code for all CPUs in the H8, H8S, H8SX family
  • Fully compatible with the ANSI/ISO:9899/1990 standard for C
    • Support for C99-language specifications(except for variable-length arrays)
    • Support for C99 libraries
      Note C99 supports H8SX and H8S families. Note, however, that programs for the H8 family cannot be compiled in the C99 language
  • Supports extended language function for H8, H8S, H8SX family
    • Intrinsic functions
    • Section address operators
    • #pragma directives
  • Support for information level message
  • Mixed source and assembler listing files
  • Supports ELF/DWARF format
  • Embedded C++ language spec-compliant class libraries
  • Expanded number of switch statement to 2048


  • Supports instructions to all CPUs in the H8, H8S, H8SX family
  • Supports assembly file inclusion
  • Supports conditional assembly
  • Supports macro in assembly
  • Supports structured assembly
  • Supports ELF/DWARF formats
  • Allows .BEQU symbol to be externally defined and referenced by using .BIMPORT and .BEXPORT

[Optimizing linkage editor]

  • Supports object file input in H8SX family
  • Compact debug information function
  • Inter-module optimization function
  • Allows multiple load module selection
  • Supports ELF/DWARF format
    • Relocatable ELF format
    • Absolute ELF format
    • S type format
    • HEX format
    • Binary format
  • Allows library files to be created and edited
  • Analysis with an output list file (outputs referenced count of symbols)
  • Checks for section address duplication

[Standard library configuration tool]

  • Allows standard library to be customized by generating the standard library in project units
  • Supports reentrant libraries
  • Variable size for malloc allocation (to save RAM capacity)
  • Variable number of open file (to save RAM capacity)

[Format converter]

  • Conversion from old format to ELF format
  • Conversion from ELF format to old format

[Stack analysis tool (CallWalker)]

  • Shows stack values in units of the C, C++ function
  • Shows stack value on module hierarchy basis
  • Edits the function allocation by drag and drop


For details, refer to the "C/C++ Compiler Package for H8SX, H8S, H8 Family Software Component List (PDF | English, 日本語)".

Target Devices, Object Format

Compile Package Version Supported Devices (MCUs) Object Format Device File Updater (Note1)
V.7 Windows version H8/300、H8/300L、H8/300H H8S/2000、H8S/2600 H8SX、AE-5 (Note2) ELF/DWARF2 Available
V.6 Windows version H8/300、H8/300L、H8/300H H8S/2000、H8S/2600 H8SX、AE-5 (Note2) ELF/DWARF2
V.6 UNIX version (Discontinued) H8/300、H8/300L、H8/300H H8S/2000、H8S/2600 H8SX、AE-5 (Note2) Unsupported
V.5 (Discontinued) H8/300、H8/300L、H8/300H H8S/2000、H8S/2600 ELF/DWARF2
V.4 (Discontinued) ELF/DWARF2
V.3 (Discontinued) SYSROF


  1. Device File Updater is a utility tool which adds or updates automatically the High-performance Embedded Workshop's source files such as a start-up routine, I/O header file, etc.
  2. The AE-5 Series MCU is supported by V.6.01 Release 00 or later. A V.6.00 user can upgrade to the latest V.6.01 free of charge.