# PVRVFrame - old bugs - ES2

**URL:** <https://forums.imgtec.com/t/pvrvframe-old-bugs-es2/1224>\
**Category:** PowerVR Insider\
**Tags:** pvrvframe\
**Created:** [October 27, 2011, 4:56pm UTC](https://forums.imgtec.com/t/pvrvframe-old-bugs-es2/1224 "2011-10-27T16:56:17Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![diafera](https://avatars.discourse-cdn.com/v4/letter/d/898d66/32.png) [@diafera](https://forums.imgtec.com/u/diafera)\
**Post date:** [October 27, 2011, 4:56pm UTC](https://forums.imgtec.com/t/pvrvframe-old-bugs-es2/1224/1 "2011-10-27T16:56:17Z")

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The follwing two bugs are still present in PVRVFrame 2.09.29.0649 (also tested on 2.8.28.\*).  
  
1. After using the glGetBooleanv(GL\_SHADER\_COMPILER,… some gl calls involving shaders starts to generate errors.

Code:

GLboolean bShaderCompiler = GL\_FALSE;  
glGetBooleanv(GL\_SHADER\_COMPILER, &bShaderCompiler); // bShaderCompiler=GL\_TRUE, err=GL\_NO\_ERROR  
GLuint vsh = glCreateShader(GL\_VERTEX\_SHADER); // err=GL\_NO\_ERROR  
GLuint fsh = glCreateShader(GL\_FRAGMENT\_SHADER); // err=GL\_NO\_ERROR  
GLboolean b1 = glIsShader(vsh); // err=GL\_INVALID\_ENUM !!!  
// PVRVFrame: "In glIsShader error: 500 (GL\_INVALID\_ENUM) : (null)"  
GLboolean b2 = glIsShader(fsh); // err=GL\_NO\_ERROR  
if (b1) glDeleteShader(vsh); // err=GL\_NO\_ERROR  
if (b2) glDeleteShader(fsh); // err=GL\_NO\_ERROR  

In the above example even a glIsShader generates an GL\_INVALID\_ENUM.  
Note that glIsShader should not rise any error flags no matter of the  
input param. Also, before that call glGetError returns GL\_NO\_ERRROR.  
  
2.&nbsp; glReleaseShaderCompiler should only generate GL\_INVALID\_OPERATION if a shader compiler is not supported. But, shader compiler is supported. glGetBooleanv(GL\_SHADER\_COMPILER, &mbShaderCompiler); returns mbShaderCompiler=GL\_TRUE and other shader related gl calls works too.  
  

Code:

glReleaseShaderCompiler(); // err=GL\_INVALID\_OPERATION !!!  
// PVRVFrame: "In glReleaseShaderCompiler error: 502 (GL\_INVALID\_OPERATION) : this function is not yet supported by the emulator"

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**Author:** ![tobias](https://avatars.discourse-cdn.com/v4/letter/t/c67d28/32.png) [@tobias](https://forums.imgtec.com/u/tobias)\
**Post date:** [October 28, 2011, 6:19am UTC](https://forums.imgtec.com/t/pvrvframe-old-bugs-es2/1224/2 "2011-10-28T06:19:43Z")

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Hi diafera,  
  
  
  
  
  
  
  
  
  
Thank you for your bug report! I’ve submitted a bug into our internal bug tracker for this and your other reports (BRN34824).  
  
  
  
  
  
  
  
Thanks,  
  
  
  
  
  
  
  
  
  
Tobias