Re: Command substitution in here-documents

[Ron Yorston <rmy@xxxxxxxxxxxx>]

Martijn Dekker wrote:
>- The error message produced can be ... interesting, e.g.:

Which leads to another thought.  'Interesting' error messages might
suggest memory issues.  And, indeed, running dash built from current
git master under Valgrind results in the following:

$ cat <<EOF
> `echo hi`
==27474== Invalid read of size 1
==27474==    at 0x4C32CC4: strcmp (vg_replace_strmem.c:846)
==27474==    by 0x40BD6C: pstrcmp (mystring.c:247)
==27474==    by 0x40BD6C: bsearch (stdlib-bsearch.h:33)
==27474==    by 0x40BD6C: findstring (mystring.c:256)
==27474==    by 0x40CFA5: findkwd (parser.c:1625)
==27474==    by 0x40CFA5: readtoken (parser.c:727)
==27474==    by 0x40D24C: peektoken (parser.c:690)
==27474==    by 0x40D24C: list.part.2 (parser.c:184)
==27474==    by 0x40E43A: list (parser.c:167)
==27474==    by 0x40E43A: readtoken1 (parser.c:1443)
==27474==    by 0x40ECE6: parseheredoc (parser.c:674)
==27474==    by 0x40D202: list.part.2 (parser.c:179)
==27474==    by 0x40AA5E: cmdloop (main.c:218)
==27474==    by 0x40211F: main (main.c:176)
==27474==  Address 0x51fb788 is 8 bytes inside a block of size 512 free'd
==27474==    at 0x4C2FDAC: free (vg_replace_malloc.c:530)
==27474==    by 0x40AE9E: popstackmark (memalloc.c:185)
==27474==    by 0x40CC14: setprompt (parser.c:1564)
==27474==    by 0x40ED69: parseheredoc (parser.c:669)
==27474==    by 0x40D202: list.part.2 (parser.c:179)
==27474==    by 0x40AA5E: cmdloop (main.c:218)
==27474==    by 0x40211F: main (main.c:176)
==27474==  Block was alloc'd at
==27474==    at 0x4C2EBAB: malloc (vg_replace_malloc.c:299)
==27474==    by 0x40AD32: ckmalloc (memalloc.c:55)
==27474==    by 0x40AD32: stalloc (memalloc.c:132)
==27474==    by 0x40AF41: growstackblock (memalloc.c:234)
==27474==    by 0x40B064: growstackto (memalloc.c:271)
==27474==    by 0x40B064: makestrspace (memalloc.c:285)
==27474==    by 0x40DD00: readtoken1 (parser.c:928)
==27474==    by 0x40EC51: expandstr (parser.c:1580)
==27474==    by 0x40CC01: setprompt (parser.c:1563)
==27474==    by 0x40ED69: parseheredoc (parser.c:669)
==27474==    by 0x40D202: list.part.2 (parser.c:179)
==27474==    by 0x40AA5E: cmdloop (main.c:218)
==27474==    by 0x40211F: main (main.c:176)
==27474== 

With commit 7c245aa reverted the Valgrind output is clean.

Ron