https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105544
--- Comment #8 from ibuclaw at gcc dot gnu.org ---
(In reply to Fabian Vogt from comment #6)
> I had a quick debugging session: The DMD lexer code doesn't really care
> about the size of the buffer and instead runs until it encounters either a 0
> or 0x1A byte. The stdin read loop in d_parse_file doesn't explicitly
> 0-terminate the buffer, which means that it works randomly...
>
OK, so the suggestion would be to zero the padding at the end of the input
buffer then.
--- a/gcc/d/d-lang.cc
+++ b/gcc/d/d-lang.cc
@@ -1072,6 +1072,10 @@ d_parse_file (void)
global.params.doHdrGeneration);
modules.push (m);
+ /* Zero the padding past the end of the buffer so the D lexer has a
+ sentinel. The lexer only reads up to 4 bytes at a time. */
+ memset (buffer + len, '\0', 16);
+
/* Overwrite the source file for the module, the one created by
Module::create would have a forced a `.d' suffix. */
m->src.length = len;
