# gl\_LastFragData cannot be respecified in PVRShaderEditor

**URL:** <https://forums.imgtec.com/t/gl-lastfragdata-cannot-be-respecified-in-pvrshadereditor/2301>\
**Category:** PowerVR Insider\
**Tags:** pvrshadereditor\
**Created:** [June 9, 2015, 1:02pm UTC](https://forums.imgtec.com/t/gl-lastfragdata-cannot-be-respecified-in-pvrshadereditor/2301 "2015-06-09T13:02:29Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![mknejp](https://sea1.discourse-cdn.com/flex015/user_avatar/forums.imgtec.com/mknejp/32/233_2.png) [@mknejp](https://forums.imgtec.com/u/mknejp)\
**Post date:** [June 9, 2015, 1:02pm UTC](https://forums.imgtec.com/t/gl-lastfragdata-cannot-be-respecified-in-pvrshadereditor/2301/1 "2015-06-09T13:02:29Z")

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Hi,

trying to redeclare the built-in gl\_LastFragData to change its precision in PVRShaderEditor 2.6 (SDK build 3.5@3523712) using the G6x00 compiler causes a compilation error.  
[pre]  
#version 100  
#extension GL\_EXT\_shader\_framebuffer\_fetch: require  
lowp vec4 gl\_LastFragData[gl\_MaxDrawBuffers];  
…  
[/pre]

This gives the error [blockquote]0:123: ‘gl\_LastFragData’ : cannot redeclare this built-in[/blockquote]

GL\_EXT\_shader\_framebuffer\_fetchHowever the description of explicitly allows the redeclaration of gl\_LastFragData. See question 3 “What is the precision of gl\_LastFragData in practice?” with the resolution “Allow redeclaration of gl\_LastFragData in order to change its precision.”.

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<div class="post-metadata">

**Author:** ![PaulLy](https://avatars.discourse-cdn.com/v4/letter/p/958977/32.png) [@PaulLy](https://forums.imgtec.com/u/PaulLy)\
**Post date:** [June 24, 2015, 8:52am UTC](https://forums.imgtec.com/t/gl-lastfragdata-cannot-be-respecified-in-pvrshadereditor/2301/2 "2015-06-24T08:52:25Z")

</div>

Thanks for you feedback. This looks like it is a GLSL compiler issue, I’ve filed a ticket on our internal issue tracker as RDI5039.