R devel - Jun 2020 - use of the tcltk package crashes R 4.0.1 for Windows

Hi,

The following code, from the examples in ?TkWidgets , immediately crashes R
4.0.1 for Windows:

--------------------- snip --------------------
library("tcltk")
tt <- tktoplevel()
label.widget <- tklabel(tt, text = "Hello, World!")
button.widget <- tkbutton(tt, text = "Push", 
	 command = function()cat("OW!\n"))
tkpack(label.widget, button.widget) # geometry manager
--------------------- snip --------------------

Session info (prior to the crash):

--------------------- snip --------------------
> sessionInfo()
R version 4.0.1 (2020-06-06)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 10 x64 (build 18363)

Matrix products: default

locale:
[1] LC_COLLATE=English_United States.1252 
[2] LC_CTYPE=English_United States.1252   
[3] LC_MONETARY=English_United States.1252
[4] LC_NUMERIC=C                          
[5] LC_TIME=English_United States.1252    

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

loaded via a namespace (and not attached):
[1] compiler_4.0.1 tools_4.0.1   
--------------------- snip --------------------

I observe this behaviour both in the Rgui and when I run R in a terminal. I
think the problem is general to the use of the tcltk package.

Best,
 John

-----------------------------------------------------------------
John Fox
Professor Emeritus
McMaster University
Hamilton, Ontario, Canada
Web: https://socialsciences.mcmaster.ca/jfox/

Not happening on Mac, so likely a Windows build issue.

(There's no 4.0.1 CRAN package yet, and no nightly build of 4.0.1 Patched,
but the only thing changed in the sources since r78644 is the VERSION file.)

-pd
> On 7 Jun 2020, at 03:13 , Fox, John <jfox at mcmaster.ca> wrote:
> 
> Hi,
> 
> The following code, from the examples in ?TkWidgets , immediately crashes R
4.0.1 for Windows:
> 
> --------------------- snip --------------------
> library("tcltk")
> tt <- tktoplevel()
> label.widget <- tklabel(tt, text = "Hello, World!")
> button.widget <- tkbutton(tt, text = "Push", 
> 	 command = function()cat("OW!\n"))
> tkpack(label.widget, button.widget) # geometry manager
> --------------------- snip --------------------
> 
> Session info (prior to the crash):
> 
> --------------------- snip --------------------
>> sessionInfo()
> R version 4.0.1 (2020-06-06)
> Platform: x86_64-w64-mingw32/x64 (64-bit)
> Running under: Windows 10 x64 (build 18363)
> 
> Matrix products: default
> 
> locale:
> [1] LC_COLLATE=English_United States.1252 
> [2] LC_CTYPE=English_United States.1252   
> [3] LC_MONETARY=English_United States.1252
> [4] LC_NUMERIC=C                          
> [5] LC_TIME=English_United States.1252    
> 
> attached base packages:
> [1] tcltk     stats     graphics  grDevices utils     datasets  methods  
> [8] base     
> 
> loaded via a namespace (and not attached):
> [1] compiler_4.0.1 tools_4.0.1   
> --------------------- snip --------------------
> 
> I observe this behaviour both in the Rgui and when I run R in a terminal. I
think the problem is general to the use of the tcltk package.
> 
> Best,
> John
> 
> -----------------------------------------------------------------
> John Fox
> Professor Emeritus
> McMaster University
> Hamilton, Ontario, Canada
> Web: https://socialsciences.mcmaster.ca/jfox/
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Office: A 4.23
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com

Just to be clear, I was talking about Mac binary packages. The one available and
tested was

R-4.0-branch
4.0.1 RC
(2020/05/30, r78644)

from mac.r-project.org. (Simon Urbanek out of office for the weekend, I
suppose.)

-pd
> On 7 Jun 2020, at 08:27 , peter dalgaard <pdalgd at gmail.com> wrote:
> 
> Not happening on Mac, so likely a Windows build issue.
> 
> (There's no 4.0.1 CRAN package yet, and no nightly build of 4.0.1
Patched, but the only thing changed in the sources since r78644 is the VERSION
file.)
> 
> -pd
> 
>> On 7 Jun 2020, at 03:13 , Fox, John <jfox at mcmaster.ca> wrote:
>> 
>> Hi,
>> 
>> The following code, from the examples in ?TkWidgets , immediately
crashes R 4.0.1 for Windows:
>> 
>> --------------------- snip --------------------
>> library("tcltk")
>> tt <- tktoplevel()
>> label.widget <- tklabel(tt, text = "Hello, World!")
>> button.widget <- tkbutton(tt, text = "Push", 
>> 	 command = function()cat("OW!\n"))
>> tkpack(label.widget, button.widget) # geometry manager
>> --------------------- snip --------------------
>> 
>> Session info (prior to the crash):
>> 
>> --------------------- snip --------------------
>>> sessionInfo()
>> R version 4.0.1 (2020-06-06)
>> Platform: x86_64-w64-mingw32/x64 (64-bit)
>> Running under: Windows 10 x64 (build 18363)
>> 
>> Matrix products: default
>> 
>> locale:
>> [1] LC_COLLATE=English_United States.1252 
>> [2] LC_CTYPE=English_United States.1252   
>> [3] LC_MONETARY=English_United States.1252
>> [4] LC_NUMERIC=C                          
>> [5] LC_TIME=English_United States.1252    
>> 
>> attached base packages:
>> [1] tcltk     stats     graphics  grDevices utils     datasets  methods
>> [8] base     
>> 
>> loaded via a namespace (and not attached):
>> [1] compiler_4.0.1 tools_4.0.1   
>> --------------------- snip --------------------
>> 
>> I observe this behaviour both in the Rgui and when I run R in a
terminal. I think the problem is general to the use of the tcltk package.
>> 
>> Best,
>> John
>> 
>> -----------------------------------------------------------------
>> John Fox
>> Professor Emeritus
>> McMaster University
>> Hamilton, Ontario, Canada
>> Web: https://socialsciences.mcmaster.ca/jfox/
>> 
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel
> 
> -- 
> Peter Dalgaard, Professor,
> Center for Statistics, Copenhagen Business School
> Solbjerg Plads 3, 2000 Frederiksberg, Denmark
> Phone: (+45)38153501
> Office: A 4.23
> Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com
> 
> 
> 
> 
> 
> 
> 
> 
> 
-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Office: A 4.23
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com

John,

The Windows installation instructions document has the following. So, one
obvious question is whether you did select it. (I haven't installed on
WIndows for ages, so I don't know whether this was changed recently or even
whether the selection is on or off by default).

-pd

Using package tcltk
==================
The package tcltk supports building graphical interfaces with Tcl/Tk.
"Support Files for Package tcltk" needs to be selected from the
installer for this to work; alternatively you can use an existing
installation of Tcl/Tk 8.6.x by following the instructions in the
rw-FAQ.



> On 7 Jun 2020, at 08:27 , peter dalgaard <pdalgd at gmail.com> wrote:
> 
> Not happening on Mac, so likely a Windows build issue.
> 
> (There's no 4.0.1 CRAN package yet, and no nightly build of 4.0.1
Patched, but the only thing changed in the sources since r78644 is the VERSION
file.)
> 
> -pd
> 
>> On 7 Jun 2020, at 03:13 , Fox, John <jfox at mcmaster.ca> wrote:
>> 
>> Hi,
>> 
>> The following code, from the examples in ?TkWidgets , immediately
crashes R 4.0.1 for Windows:
>> 
>> --------------------- snip --------------------
>> library("tcltk")
>> tt <- tktoplevel()
>> label.widget <- tklabel(tt, text = "Hello, World!")
>> button.widget <- tkbutton(tt, text = "Push", 
>> 	 command = function()cat("OW!\n"))
>> tkpack(label.widget, button.widget) # geometry manager
>> --------------------- snip --------------------
>> 
>> Session info (prior to the crash):
>> 
>> --------------------- snip --------------------
>>> sessionInfo()
>> R version 4.0.1 (2020-06-06)
>> Platform: x86_64-w64-mingw32/x64 (64-bit)
>> Running under: Windows 10 x64 (build 18363)
>> 
>> Matrix products: default
>> 
>> locale:
>> [1] LC_COLLATE=English_United States.1252 
>> [2] LC_CTYPE=English_United States.1252   
>> [3] LC_MONETARY=English_United States.1252
>> [4] LC_NUMERIC=C                          
>> [5] LC_TIME=English_United States.1252    
>> 
>> attached base packages:
>> [1] tcltk     stats     graphics  grDevices utils     datasets  methods
>> [8] base     
>> 
>> loaded via a namespace (and not attached):
>> [1] compiler_4.0.1 tools_4.0.1   
>> --------------------- snip --------------------
>> 
>> I observe this behaviour both in the Rgui and when I run R in a
terminal. I think the problem is general to the use of the tcltk package.
>> 
>> Best,
>> John
>> 
>> -----------------------------------------------------------------
>> John Fox
>> Professor Emeritus
>> McMaster University
>> Hamilton, Ontario, Canada
>> Web: https://socialsciences.mcmaster.ca/jfox/
>> 
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel
> 
> -- 
> Peter Dalgaard, Professor,
> Center for Statistics, Copenhagen Business School
> Solbjerg Plads 3, 2000 Frederiksberg, Denmark
> Phone: (+45)38153501
> Office: A 4.23
> Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com
> 
> 
> 
> 
> 
> 
> 
> 
> 
-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Office: A 4.23
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com

On Sun, Jun 7, 2020 at 3:13 AM Fox, John <jfox at mcmaster.ca>
wrote:
>
> Hi,
>
> The following code, from the examples in ?TkWidgets , immediately crashes R
4.0.1 for Windows:
>
> --------------------- snip --------------------
> library("tcltk")
> tt <- tktoplevel()
> label.widget <- tklabel(tt, text = "Hello, World!")
> button.widget <- tkbutton(tt, text = "Push",
>          command = function()cat("OW!\n"))
> tkpack(label.widget, button.widget) # geometry manager
> --------------------- snip --------------------

I can reproduce this. The backtrace shows the crash happens in
dotTclObjv  [/src/library/tcltk/src/tcltk.c at 243 ]. This looks like a
bug that was introduced by commit 78408/78409 about a month ago. I
think the problem is that this commit changes 'calloc' to
'Calloc'
without changing the corresponding 'free' to 'Free'.

This has nothing to do with the Windows build or installation. Nothing
has changed in the windows build procedure between 4.0.0 and 4.0.1.

Dear Jeroen,

Thank you for tracking down the source of the problem.

You probably saw that Peter Dalgaard reported that the tcltk package apparently
is working fine in R 4.0.1 on macOS. I haven't confirmed that myself because
the Mac binary for R 4.0.1 isn't yet on CRAN.

Best,
 John
> On Jun 7, 2020, at 10:00 AM, Jeroen Ooms <jeroenooms at gmail.com>
wrote:
> 
> On Sun, Jun 7, 2020 at 3:13 AM Fox, John <jfox at mcmaster.ca> wrote:
>> 
>> Hi,
>> 
>> The following code, from the examples in ?TkWidgets , immediately
crashes R 4.0.1 for Windows:
>> 
>> --------------------- snip --------------------
>> library("tcltk")
>> tt <- tktoplevel()
>> label.widget <- tklabel(tt, text = "Hello, World!")
>> button.widget <- tkbutton(tt, text = "Push",
>>         command = function()cat("OW!\n"))
>> tkpack(label.widget, button.widget) # geometry manager
>> --------------------- snip --------------------
> 
> 
> I can reproduce this. The backtrace shows the crash happens in
> dotTclObjv  [/src/library/tcltk/src/tcltk.c at 243 ]. This looks like a
> bug that was introduced by commit 78408/78409 about a month ago. I
> think the problem is that this commit changes 'calloc' to
'Calloc'
> without changing the corresponding 'free' to 'Free'.
> 
> This has nothing to do with the Windows build or installation. Nothing
> has changed in the windows build procedure between 4.0.0 and 4.0.1.

On 07/06/2020 10:00 a.m., Jeroen Ooms wrote:
> On Sun, Jun 7, 2020 at 3:13 AM Fox, John <jfox at mcmaster.ca> wrote:
>>
>> Hi,
>>
>> The following code, from the examples in ?TkWidgets , immediately
crashes R 4.0.1 for Windows:
>>
>> --------------------- snip --------------------
>> library("tcltk")
>> tt <- tktoplevel()
>> label.widget <- tklabel(tt, text = "Hello, World!")
>> button.widget <- tkbutton(tt, text = "Push",
>>           command = function()cat("OW!\n"))
>> tkpack(label.widget, button.widget) # geometry manager
>> --------------------- snip --------------------
> 
> 
> I can reproduce this. The backtrace shows the crash happens in
> dotTclObjv  [/src/library/tcltk/src/tcltk.c at 243 ]. This looks like a
> bug that was introduced by commit 78408/78409 about a month ago. I
> think the problem is that this commit changes 'calloc' to
'Calloc'
> without changing the corresponding 'free' to 'Free'.
The same commit made the same kind of change to unix/sys-std.c as well.

Duncan Murdoch
> 
> This has nothing to do with the Windows build or installation. Nothing
> has changed in the windows build procedure between 4.0.0 and 4.0.1.
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>

So this wasn't tested for a month?

Anyways, Free() is just free() with a check that we're not freeing a null
pointer, followed by setting the pointer to NULL. At that point of tcltk.c, we
have

   for (objc = i = 0; i < length(avec); i++){
        const char *s;
        char *tmp;
        if (!isNull(nm) && strlen(s = translateChar(STRING_ELT(nm,
i)))){
            //  tmp = calloc(strlen(s)+2, sizeof(char));
            tmp = Calloc(strlen(s)+2, char);
            *tmp = '-';
            strcpy(tmp+1, s);
            objv[objc++] = Tcl_NewStringObj(tmp, -1);
            free(tmp);
        }
        if (!isNull(t = VECTOR_ELT(avec, i)))
            objv[objc++] = (Tcl_Obj *) R_ExternalPtrAddr(t);
    }

and I can't see how tmp can be NULL at the free(), nor can I see it
mattering if it is not set to NULL (notice that it goes out of scope with the
for loop).

-pd
 
> On 7 Jun 2020, at 16:00 , Jeroen Ooms <jeroenooms at gmail.com>
wrote:
> 
> On Sun, Jun 7, 2020 at 3:13 AM Fox, John <jfox at mcmaster.ca> wrote:
>> 
>> Hi,
>> 
>> The following code, from the examples in ?TkWidgets , immediately
crashes R 4.0.1 for Windows:
>> 
>> --------------------- snip --------------------
>> library("tcltk")
>> tt <- tktoplevel()
>> label.widget <- tklabel(tt, text = "Hello, World!")
>> button.widget <- tkbutton(tt, text = "Push",
>>         command = function()cat("OW!\n"))
>> tkpack(label.widget, button.widget) # geometry manager
>> --------------------- snip --------------------
> 
> 
> I can reproduce this. The backtrace shows the crash happens in
> dotTclObjv  [/src/library/tcltk/src/tcltk.c at 243 ]. This looks like a
> bug that was introduced by commit 78408/78409 about a month ago. I
> think the problem is that this commit changes 'calloc' to
'Calloc'
> without changing the corresponding 'free' to 'Free'.
> 
> This has nothing to do with the Windows build or installation. Nothing
> has changed in the windows build procedure between 4.0.0 and 4.0.1.
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Office: A 4.23
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com