From: Steve Jacobson <sjac3@leland.Stanford.EDU>
Subject: newly revised hw1b nightmare grammar
To: zelenski@CS.Stanford.EDU, sjac3@leland.Stanford.EDU, sjacobso@cisco.com
Date: Mon, 27 Apr 1998 13:05:09 -0700 (PDT)
X-Mailer: ELM [version 2.4 PL25]


The hw1b nightmare grammar (newly revised).

This was inspired by a fitful night of half-sleep before hw1b
was due.  I spent a very long evening writing the darray.c code,
and then had a segmentation fault I was too tired to track down.
I ended up debugging code all night in my sleep, dreaming about
the most bizarre and inconsequential things that could be wrong
(none of which were, of course).

SteveJ


{
<start> 
<code-phrase> <failure-reason> because it went <initial-pointer-problem>  
So I ran it under gdb, but <gdb-problem>  So I tried Purify, which told me
<purify-problem>  I've got to remember to <general-lament> 	;
}

{
<code-phrase>
My <my-code-name> code			;
My <my-code-name> code			;
The example search code			;
The <supplied-code-name> they gave us	;
The provided <supplied-code-name>	;
My <my-code-name> code			;
My <my-code-name> code			;
}

{
<my-files>
<my-code-name>		;
<my-headers-name>	;
}

{
<my-code-name>
DArray		;
HashTable	;
old scanner	;
darray.c	;
search.c	;
hashtable.c	;
old scanner.c	;
}

{
<my-headers-name>
darray.h	;
search.h	;
hashtable.h	;
old scanner.h	;
}

{
<supplied-code-name>
scanner.o	;
darray.o	;
hashtable.o	;
old scanner.c	;
}

{
<failure-reason>
got a segfault 					;
had a bus error 				;
had an alignment error 				;
just hung 					;
went off in the weeds somewhere 		;
went out to lunch 				;
crashed in a spectacular ball of fire 		;
ate the big one and died 			;
went into a death spiral 			;
collapsed in a pile of smoldering wreckage 	;
asserted again 					;
spewed these really bizarre messages 		;
}

{
<initial-pointer-problem>
<initial-pointer-action>      <pointer-type>    <pointer-problem>	;
}

{
<pointer-problem>
<pointer-action>      <pointer-type>    <pointer-problem>	;
<pointer-action>      <pointer-type>    <pointer-problem>	;
<pointer-action>      <pointer-type>    <pointer-problem>	;
<pointer-action>      <pointer-type>    <pointer-problem>	;
<pointer-action>      <pointer-type>    <pointer-problem>	;
and finally dereferenced a NULL *.				;
and ended up calling a NULL function.				;
}

{
<initial-pointer-action>
to a				;
through a			;
dereferencing a			;
}

{
<pointer-action>
<initial-pointer-action>	;
<initial-pointer-action>	;
which was really a		;
which should have been a	;
}

{
<pointer-type>
char  **			;
HashTable  *			;
DArray  *			;
void  *				;
darray  []			;
hasharray  []			;
}

{
<gdb-problem>
I can't remember <gdb-action> <gdb-result> and <gdb-problem>	;
I wish I knew <gdb-action> <gdb-result> and <gdb-problem>	;
why won't it <gdb-result> and <gdb-problem>			;
I forget where I put that darn gdb handout.			;
I wonder where I put my gdb book.				;
}

{
<gdb-action>
the command to		;
the syntax to		;
how to			;
the right way to	;
the best way to		;
any way to		;
}

{
<gdb-result>
clear the breakpoints		;
dump the local variables	;
dump the parameters		;
step out of the function	;
show the stack trace		;
stop before the crash		;
}

{
<purify-problem>
I had <purify-error> and <purify-problem>			;
there's <purify-error> and <purify-problem>			;
for some reason I got <purify-error> and <purify-problem>	;
I have to deal with <purify-error> and <purify-problem>		;
I leaked  _all_ my memory.					;
I leaked 100 percent of my memory.				;
}

{
<purify-error>
a UMR error			;
an ABR error			;
an ABW error			;
an NPR radio error		;
an NPW error			;
a BSR error			;
a BSW error			;
a FEE FIE FOE FUM error		;
a FMR error			;
a FMW error			;
a FNH error			;
}

{
<general-lament>
add some more comments to <my-files> and <general-lament>		;
try and get some sleep, and <general-lament>				;
try and use only one late day, and <general-lament>			;
walk through the <my-code-name> code and <general-lament>		;
use a Scanner for stdin, and <general-lament>				;
clean up <my-code-name> a bit and <general-lament>			;
put those grotesque casts in a helper function, and <general-lament>	;
pull that ugly hack out of <my-code-name> and <general-lament>		;
read the header files just one more time.				;
}