# Compile Error: Definition Provided for Explicit instantiation
**URL:** https://discourse.vtk.org/t/compile-error-definition-provided-for-explicit-instantiation/3176
**Category:** Support
**Created:** [April 29, 2020, 7:45am UTC](https://discourse.vtk.org/t/compile-error-definition-provided-for-explicit-instantiation/3176 "2020-04-29T07:45:05Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@FabianSchuetze](https://discourse.vtk.org/u/FabianSchuetze)
#### Post date: [April 29, 2020, 7:45am UTC](https://discourse.vtk.org/t/compile-error-definition-provided-for-explicit-instantiation/3176/1 "2020-04-29T07:45:05Z")
When compiling software that includes `vtkFloatArray.h` with Qtcreator and gcc 9.3 as compiler on Ubuntu 20.04 I receive the following error:
```
/usr/local/include/vtk-8.2/vtkFloatArray.h:38:3: error: definition provided for explicit instantiation
38 | vtkTypeMacro(vtkFloatArray, vtkDataArray)
| ^ ~~~~~~~~~~~
```
The code highlighted is:
```
class VTKCOMMONCORE_EXPORT vtkFloatArray : public vtkDataArray
{
public:
vtkTypeMacro(vtkFloatArray, vtkDataArray)
```
I also tried to compile this code on Windows with VisualStudio 2019 I didn’t receive this error.
Does somebody kindly have any idea what this error means?
---
### Author:  [@ben.boeckel](https://discourse.vtk.org/u/ben.boeckel)
#### Post date: [April 29, 2020, 12:53pm UTC](https://discourse.vtk.org/t/compile-error-definition-provided-for-explicit-instantiation/3176/2 "2020-04-29T12:53:18Z")
@RobertMaynard @AllisonVacanti @allison.vacanti (not sure which one is the active account)
---
### Author:  [@amaclean](https://discourse.vtk.org/u/amaclean)
#### Post date: [April 30, 2020, 2:13am UTC](https://discourse.vtk.org/t/compile-error-definition-provided-for-explicit-instantiation/3176/3 "2020-04-30T02:13:45Z")
The master version of VTK builds ok with no errors with gcc 9.3 on Ubuntu 20.04. So this is most likely a vtk-8.2 issue.
---
### Author:  [@FabianSchuetze](https://discourse.vtk.org/u/FabianSchuetze)
#### Post date: [April 30, 2020, 5:37am UTC](https://discourse.vtk.org/t/compile-error-definition-provided-for-explicit-instantiation/3176/4 "2020-04-30T05:37:53Z")
Thank you for the confirmation, @Andrew. I will thus investigate a bit more and see whether there might be some setting on my system that cause the problem.
---
### Author:  [@FabianSchuetze](https://discourse.vtk.org/u/FabianSchuetze)
#### Post date: [April 30, 2020, 8:06am UTC](https://discourse.vtk.org/t/compile-error-definition-provided-for-explicit-instantiation/3176/5 "2020-04-30T08:06:41Z")
Thank you again @Andrew for your help. I realized this was a problem on my system. Thanks for your help and for checking.
---
### Author:  [@amaclean](https://discourse.vtk.org/u/amaclean)
#### Post date: [April 30, 2020, 8:58am UTC](https://discourse.vtk.org/t/compile-error-definition-provided-for-explicit-instantiation/3176/6 "2020-04-30T08:58:21Z")
Glad to help. I’m pleased you solved it.