R devel - May 2020 - Graphic parameters with length zero in grid cause R to crash

Hi,


I found in grid package, if the graphic parameters have zero length, R crashes.
In the

following code, I only tested `grid.rect()` and the `fill` parameter, but I
think it should

be similar as other grid graphic functions.


In `gpar()` function, the graphic parameters are not allowed to have zero
length, but
we can make them with zero length by first generating a `gpar` object and then
subsetting
with zero length index, such as follows:

```
> library(grid)
> gp = gpar(fill = 1)
> grid.rect(gp = gp[integer(0)])
```

After Executing the code, R crashes with message "Floating point exception:
8?".

If I set the value of `fill` to an integer, the following code causes an error
with a
not informative error message.
> library(grid)
> gp = gpar(fill = as.integer(1))
> grid.rect(gp = gp[integer(0)])
Error in grid.Call.graphics(C_rect, x$x, x$y, x$width, x$height,
resolveHJust(x$just,  :
  numerical color values must be >= 0, found -192882464

But sometimes it also causes R to crash.


My session info:


```
> sessionInfo()
R version 4.0.0 (2020-04-24)
Platform: x86_64-apple-darwin17.0 (64-bit)
Running under: macOS Catalina 10.15.4

Matrix products: default
BLAS:  
/Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRblas.dylib
LAPACK:
/Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRlapack.dylib

locale:
[1] en_GB.UTF-8/en_GB.UTF-8/en_GB.UTF-8/C/en_GB.UTF-8/en_GB.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base

other attached packages:
[1] colorout_1.2-2

loaded via a namespace (and not attached):
[1] compiler_4.0.0?
```


Best regards,
Zuguang Gu?


	[[alternative HTML version deleted]]

Reproduced on latest Catalina beta and R 4.0.0 and latest RStudio
devel build (it crashes the session).

On Tue, May 19, 2020 at 7:39 AM Gu, Zuguang <z.gu at dkfz-heidelberg.de>
wrote:
>
> Hi,
>
>
> I found in grid package, if the graphic parameters have zero length, R
crashes. In the
>
> following code, I only tested `grid.rect()` and the `fill` parameter, but I
think it should
>
> be similar as other grid graphic functions.
>
>
> In `gpar()` function, the graphic parameters are not allowed to have zero
length, but
> we can make them with zero length by first generating a `gpar` object and
then subsetting
> with zero length index, such as follows:
>
> ```
> > library(grid)
> > gp = gpar(fill = 1)
> > grid.rect(gp = gp[integer(0)])
> ```
>
> After Executing the code, R crashes with message "Floating point
exception: 8?".
>
> If I set the value of `fill` to an integer, the following code causes an
error with a
> not informative error message.
>
> > library(grid)
> > gp = gpar(fill = as.integer(1))
> > grid.rect(gp = gp[integer(0)])
> Error in grid.Call.graphics(C_rect, x$x, x$y, x$width, x$height,
resolveHJust(x$just,  :
>   numerical color values must be >= 0, found -192882464
>
> But sometimes it also causes R to crash.
>
>
> My session info:
>
>
> ```
>
> > sessionInfo()
> R version 4.0.0 (2020-04-24)
> Platform: x86_64-apple-darwin17.0 (64-bit)
> Running under: macOS Catalina 10.15.4
>
> Matrix products: default
> BLAS:  
/Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRblas.dylib
> LAPACK:
/Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRlapack.dylib
>
> locale:
> [1] en_GB.UTF-8/en_GB.UTF-8/en_GB.UTF-8/C/en_GB.UTF-8/en_GB.UTF-8
>
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
>
> other attached packages:
> [1] colorout_1.2-2
>
> loaded via a namespace (and not attached):
> [1] compiler_4.0.0?
> ```
>
>
> Best regards,
> Zuguang Gu?
>
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel

Yeah, that seems not good.

I will take a look.

Thanks for the report!

Paul

On 19/05/20 9:26 pm, Gu, Zuguang wrote:
> Hi,
> 
> 
> I found in grid package, if the graphic parameters have zero length, R
crashes. In the
> 
> following code, I only tested `grid.rect()` and the `fill` parameter, but I
think it should
> 
> be similar as other grid graphic functions.
> 
> 
> In `gpar()` function, the graphic parameters are not allowed to have zero
length, but
> we can make them with zero length by first generating a `gpar` object and
then subsetting
> with zero length index, such as follows:
> 
> ```
>> library(grid)
>> gp = gpar(fill = 1)
>> grid.rect(gp = gp[integer(0)])
> ```
> 
> After Executing the code, R crashes with message "Floating point
exception: 8?".
> 
> If I set the value of `fill` to an integer, the following code causes an
error with a
> not informative error message.
> 
>> library(grid)
>> gp = gpar(fill = as.integer(1))
>> grid.rect(gp = gp[integer(0)])
> Error in grid.Call.graphics(C_rect, x$x, x$y, x$width, x$height,
resolveHJust(x$just,  :
>    numerical color values must be >= 0, found -192882464
> 
> But sometimes it also causes R to crash.
> 
> 
> My session info:
> 
> 
> ```
> 
>> sessionInfo()
> R version 4.0.0 (2020-04-24)
> Platform: x86_64-apple-darwin17.0 (64-bit)
> Running under: macOS Catalina 10.15.4
> 
> Matrix products: default
> BLAS:  
/Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRblas.dylib
> LAPACK:
/Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRlapack.dylib
> 
> locale:
> [1] en_GB.UTF-8/en_GB.UTF-8/en_GB.UTF-8/C/en_GB.UTF-8/en_GB.UTF-8
> 
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
> 
> other attached packages:
> [1] colorout_1.2-2
> 
> loaded via a namespace (and not attached):
> [1] compiler_4.0.0?
> ```
> 
> 
> Best regards,
> Zuguang Gu?
> 
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
> 
-- 
Dr Paul Murrell
Department of Statistics
The University of Auckland
Private Bag 92019
Auckland
New Zealand
64 9 3737599 x85392
paul at stat.auckland.ac.nz
http://www.stat.auckland.ac.nz/~paul/