Re: Uninitialized variable sometimes causing malformed TFM files
Marcel Krüger <[email protected]> Wed, 20 Mar 2019 20:26:22 +0100
| Newsgroups | gmane.comp.tex.metapost |
|---|---|
| Message-ID | <[email protected]> |
---- On Wed, 20 Mar 2019 19:01:08 +0100 luigi scarso <[email protected]> wrote ---- > > > On Wed, Mar 20, 2019 at 6:54 PM Marcel Krüger <[email protected]> wrote: > ---- On Wed, 20 Mar 2019 18:29:09 +0100 luigi scarso <[email protected]> wrote ---- > > > > > > On Sat, Mar 16, 2019 at 6:04 PM Marcel Krüger <[email protected]> wrote: > > > > sorry for delay, I will it asap. -- > > luigi > > Thanks. There is one other thing, I do not really know if I would describe it as a backward compatibility bug or a feature request: > > For non-"scaled" numbersystems, code like > > filldraw stroke z1e--z2e; > (example taken from cmbase.mf, `left_bracket`) > > fail, because z1e-- is interpreted as z 1e- - instead of z1e --. So z1e--z2e is equal to z1-z2e, leading to lots of errors. > > I understand that the new numbersystems and the exponential syntax can lead to problems of this kind, but I think this could be avoided: > Maybe a `e+` / `e-` could only be interpreted as exponential notation if it is followed by a digit? I do not think > anyone would write "1e-" or "3e+" for 1 or 3, so it should not lead to any breakage. > On the other hand it would catch almost all cases where this is invoked accidentially. > > A possible implementation of this change is attached. > > > hm it looks like a serious bug, and I fear I will not able to fix it for next TL --- but I hope to put it into trunk immediately after the TL code is frozen. > Right, I am sorry for bringing this up so late in the TL cycle. One additional note on this: The behaviour described above (`1e-` being interpreted as `1`) seems to be specific to the `double` mode. The `decimal` mode just fails because it is not able to parse the number, which further reduces the risk of breaking some code by changing the current behaviour. Also I attached a fixed version of the earlier patch, there was a smaller error. Best regards, Marcel Krüger > > -- > luigi > -- http://tug.org/metapost/
MP-digit-change.diff
(application/octet-stream, 2.1 KB)
diff --git a/source/texk/web2c/mplibdir/mpmathbinary.w b/source/texk/web2c/mplibdir/mpmathbinary.w
index a4312c52c..b5a2da736 100644
--- a/source/texk/web2c/mplibdir/mpmathbinary.w
+++ b/source/texk/web2c/mplibdir/mpmathbinary.w
@@ -982,6 +982,10 @@ static void find_exponent (MP mp) {
if (mp->buffer[mp->cur_input.loc_field] == '+' ||
mp->buffer[mp->cur_input.loc_field] == '-') {
mp->cur_input.loc_field++;
+ if (mp->char_class[mp->buffer[mp->cur_input.loc_field]] != digit_class) {
+ mp->cur_input.loc_field -= 2;
+ return;
+ }
}
while (mp->char_class[mp->buffer[mp->cur_input.loc_field]] == digit_class) {
mp->cur_input.loc_field++;
diff --git a/source/texk/web2c/mplibdir/mpmathdecimal.w b/source/texk/web2c/mplibdir/mpmathdecimal.w
index 2ddc21647..b9971a914 100644
--- a/source/texk/web2c/mplibdir/mpmathdecimal.w
+++ b/source/texk/web2c/mplibdir/mpmathdecimal.w
@@ -1073,6 +1073,10 @@ static void find_exponent (MP mp) {
if (mp->buffer[mp->cur_input.loc_field] == '+' ||
mp->buffer[mp->cur_input.loc_field] == '-') {
mp->cur_input.loc_field++;
+ if (mp->char_class[mp->buffer[mp->cur_input.loc_field]] != digit_class) {
+ mp->cur_input.loc_field -= 2;
+ return;
+ }
}
while (mp->char_class[mp->buffer[mp->cur_input.loc_field]] == digit_class) {
mp->cur_input.loc_field++;
diff --git a/source/texk/web2c/mplibdir/mpmathdouble.w b/source/texk/web2c/mplibdir/mpmathdouble.w
index cb1496936..c305cf290 100644
--- a/source/texk/web2c/mplibdir/mpmathdouble.w
+++ b/source/texk/web2c/mplibdir/mpmathdouble.w
@@ -705,6 +705,10 @@ static void find_exponent (MP mp) {
}
if (mp->buffer[mp->cur_input.loc_field] == '+' ||
mp->buffer[mp->cur_input.loc_field] == '-') {
mp->cur_input.loc_field++;
+ if (mp->char_class[mp->buffer[mp->cur_input.loc_field]] != digit_class) {
+ mp->cur_input.loc_field -= 2;
+ return;
+ }
}
while (mp->char_class[mp->buffer[mp->cur_input.loc_field]] == digit_class) {