"fc -l" broken between v0.5.5.1 and v0.5.6

Hello,

When building with libedit, I get the following behavior:

% ./src/dash -E

$ fc -l
fc: 1: history number -16 not found (internal error)
$

dialling back to v0.5.5.1:

% ./src/dash -E

$ fc -l
    1 fc -l
$

It's totally invisible to me the cause of this regression, otherwise I would have also included a patch!

This occurs on both darwin and centos 5.3.

Let me know if I can provide more information,

--Wez.

Please bisect this to find the commit that introduced the problem. See git help bisect or
http://www.kernel.org/pub/software/scm/git/docs/git-bisect-lk2009.html .

Jilles Tjoelker

0df96793ef6aa103df228d7dfe56099b7d721a15 is first bad commit commit 0df96793ef6aa103df228d7dfe56099b7d721a15

Author: Rocky Bernstein <[email protected]>
Date:   Tue Aug 11 15:59:33 2009 +1000

[SHELL] Add preliminary LINENO support

Looks like in contrast to what the dash.1 manual page says, expansion of PS{1,2,4} does work.

Here is a little patch to set LINENO. The ways in that it is less than ideal mirror the ways that the line number error reporting is also less than ideal.

For example if you run this:

(
x=$((1/0))
# Just to add another line
# And another
) # error reports this line

The error reported will be the closing parenthesis even though I think most people would prefer the error to be the one where x was set.

% git bisect log
# bad: [02a568bb1466de25e9749ee7f501524f9e76c503] Release 0.5.6. # good: [6045fe25078345074f027312d106d3fc19df56e5] Release 0.5.5.1. git bisect start 'v0.5.6' 'v0.5.5.1'
# bad: [d53f173bb00bcc1d89ceb9e82b7d7e2b2a8dd852] [EVAL] Revert SKIPEVAL into EXEXIT
git bisect bad d53f173bb00bcc1d89ceb9e82b7d7e2b2a8dd852
# good: [956b4bd209a9d17613e419e2b50e0f533600497b] [MAN] Update manual page to differentiate dash from ash
git bisect good 956b4bd209a9d17613e419e2b50e0f533600497b
# good: [55c46b7286f5d9f2d8291158203e2b61d2494420] [BUILTIN] Honor tab as IFS whitespace when splitting fields in readcmd
git bisect good 55c46b7286f5d9f2d8291158203e2b61d2494420
# bad: [68097929869a3a3e511ac2e2c3d9dc3730652286] [EVAL] Pass EV_TESTED into evalcmd
git bisect bad 68097929869a3a3e511ac2e2c3d9dc3730652286
# bad: [0df96793ef6aa103df228d7dfe56099b7d721a15] [SHELL] Add preliminary LINENO support
git bisect bad 0df96793ef6aa103df228d7dfe56099b7d721a15

Digging into this, if I remove the initialization of the LINENO variable, "fc -l" no longer reports an error:

index 2737fb1..fd206df 100644
@@ -90,7 +90,7 @@ struct var varinit[] = {
        { 0,    VSTRFIXED|VTEXTFIXED,           "PS2=> ",       0 },
        { 0,    VSTRFIXED|VTEXTFIXED,           "PS4=+ ",       0 },
        { 0,    VSTRFIXED|VTEXTFIXED,           "OPTIND=1",     getoptsreset },
-       { 0,    VSTRFIXED|VTEXTFIXED,           "LINENO=1",     0 },
+//     { 0,    VSTRFIXED|VTEXTFIXED,           "LINENO=1",     0 },
 #ifndef SMALL
        { 0,    VSTRFIXED|VTEXTFIXED|VUNSET,    "TERM\0",       0 },
        { 0,    VSTRFIXED|VTEXTFIXED|VUNSET,    "HISTSIZE\0",   sethistsize },

I'm at a loss to explain this, but having done the legwork, I'll let you folks figure out how to fix it.

--Wez.

Git commit 0df96793ef6aa103df228d7dfe56099b7d721a15 "[SHELL] Add preliminary LINENO support" added the LINENO variable in the middle of other initialized variables, causing some macros for TERM and HISTSIZE to break (both of these are only used if libedit support is compiled in, which is not the case by default).

The breakage is the same as can be seen by setting HISTSIZE=0.

Also add a comment warning about this.

The breakage was reported by Wez Furlong.

---
 src/var.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

index 3efc943..25c2216 100644
@@ -78,6 +78,7 @@ const char defifsvar[] = "IFS= \t\n";
 const char defifs[] = " \t\n";
 #endif
 
+/* Some macros in var.h depend on the order, add new variables to the end. */
 struct var varinit[] = {
 #if ATTY
 	{ 0,	VSTRFIXED|VTEXTFIXED|VUNSET,	"ATTY\0",	0 },

@@ -94,11 +95,11 @@ struct var varinit[] = {
 	{ 0,	VSTRFIXED|VTEXTFIXED,		"PS2=> ",	0 },
 	{ 0,	VSTRFIXED|VTEXTFIXED,		"PS4=+ ",	0 },
 	{ 0,	VSTRFIXED|VTEXTFIXED,		"OPTIND=1",	getoptsreset },
-	{ 0,	VSTRFIXED|VTEXTFIXED,		"LINENO=1",	0 },
 #ifndef SMALL
 	{ 0,	VSTRFIXED|VTEXTFIXED|VUNSET,	"TERM\0",	0 },
 	{ 0,	VSTRFIXED|VTEXTFIXED|VUNSET,	"HISTSIZE\0",	sethistsize },
 #endif
+	{ 0,	VSTRFIXED|VTEXTFIXED,		"LINENO=1",	0 },
 };
 
 STATIC struct var *vartab[VTABSIZE];

1.7.1.1

Patch applied. Thanks Jilles!

Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt