# Freedom Studio Compiler Options for HiFive1 Rev B

**URL:** <https://forums.sifive.com/t/freedom-studio-compiler-options-for-hifive1-rev-b/2612>\
**Category:** HiFive1 Rev B\
**Created:** [July 10, 2019, 2:53pm UTC](https://forums.sifive.com/t/freedom-studio-compiler-options-for-hifive1-rev-b/2612 "2019-07-10T14:53:53Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![3pidemix](https://avatars.discourse-cdn.com/v4/letter/3/dfb087/32.png) [@3pidemix](https://forums.sifive.com/u/3pidemix)\
**Post date:** [July 10, 2019, 2:53pm UTC](https://forums.sifive.com/t/freedom-studio-compiler-options-for-hifive1-rev-b/2612/1 "2019-07-10T14:53:53Z")

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I’m attempting to modify the example hello and coremark projects to emit only 32-bit code and I’m having a tough time figuring out how to generate builds that don’t used compressed instructions. The Eclipse compiler settings are usually under Properties-\>C/C++ Build-\>Settings, but I’m not seeing this anywhere. How can I modify this? Is there a way to tell the build system to only generate 32-bit instructions?

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**Author:** ![DrewatSiFive](https://avatars.discourse-cdn.com/v4/letter/d/58f4c7/32.png) [@DrewatSiFive](https://forums.sifive.com/u/DrewatSiFive)\
**Post date:** [July 10, 2019, 3:06pm UTC](https://forums.sifive.com/t/freedom-studio-compiler-options-for-hifive1-rev-b/2612/2 "2019-07-10T15:06:01Z")

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Freedom Studio now uses makefile projects. The ISA string can be edited by opening up the settings.mk file in the bsp/sifive-hifive1-revb folder and editing the RISCV\_ARCH variable to the desired ISA.

For example chaning it RISCV\_ARCH=rv32im should to the trick.

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**Author:** ![3pidemix](https://avatars.discourse-cdn.com/v4/letter/3/dfb087/32.png) [@3pidemix](https://forums.sifive.com/u/3pidemix)\
**Post date:** [July 10, 2019, 3:16pm UTC](https://forums.sifive.com/t/freedom-studio-compiler-options-for-hifive1-rev-b/2612/3 "2019-07-10T15:16:21Z")

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Thanks! That did the trick - I had initially tried just stripping the “c” from RISCV\_ARCH, but was getting configuration errors. I guess the atomic instructions require “c” as well? At any rate, that works. Thanks again!