> On 19/04/2021 19:50 Iain Buclaw <ibuc...@gdcproject.org> wrote:
>
>
> Hi,
>
> This patch fixes an ICE that occurred in the D front-end diagnostic
> handlers. The percentage character was being confused for a format
> specifier in pp_format(), whilst the backtick character was confused for
> the beginning of a quoted string in expand_d_format().
>
> Both are now properly escaped to avoid the ICE.
>
> Bootstrapped and regression tested on x86_64-linux-gnu/-m32/-mx32, and
> committed to mainline.
>
> Will also be preparing a backport to the gcc-10 and gcc-9 release
> branches, as the bug is reproducible there as well.
Attached backport, regression tested and applied to both releases/gcc-9
and releases/gcc-10 branches.
Regards,
Iain.
---
gcc/d/ChangeLog:
PR d/98457
* d-diagnostic.cc (expand_d_format): Handle escaped backticks.
(escape_d_format): New funtion.
(verror): Call escape_d_format on prefixing strings.
(vdeprecation): Likewise.
gcc/testsuite/ChangeLog:
PR d/98457
* gdc.dg/pr98457.d: New test.
(cherry picked from commit dc7d1c74ffb1cc85e67984632f581d526c783770)
---
gcc/d/d-diagnostic.cc | 64 +++++++++++++++++++++++++++++++---
gcc/testsuite/gdc.dg/pr98457.d | 9 +++++
2 files changed, 68 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/gdc.dg/pr98457.d
diff --git a/gcc/d/d-diagnostic.cc b/gcc/d/d-diagnostic.cc
index 95a008d1b6f..47c7323aa0b 100644
--- a/gcc/d/d-diagnostic.cc
+++ b/gcc/d/d-diagnostic.cc
@@ -48,7 +48,7 @@ expand_d_format (const char *format)
for (const char *p = format; *p;)
{
- while (*p != '\0' && *p != '%' && *p != '`')
+ while (*p != '\0' && *p != '\\' && *p != '%' && *p != '`')
{
buf.writeByte (*p);
p++;
@@ -57,6 +57,21 @@ expand_d_format (const char *format)
if (*p == '\0')
break;
+ if (*p == '\\')
+ {
+ if (p[1] == '`')
+ {
+ /* Escaped backtick, don't expand it as a quoted string. */
+ buf.writeByte ('`');
+ p++;;
+ }
+ else
+ buf.writeByte (*p);
+
+ p++;
+ continue;
+ }
+
if (*p == '`')
{
/* Text enclosed by `...` are translated as a quoted string. */
@@ -113,6 +128,43 @@ expand_d_format (const char *format)
return buf.extractString ();
}
+/* Rewrite the format string FORMAT to deal with any characters that require
+ escaping before expand_d_format expands it. */
+
+static char *
+escape_d_format (const char *format)
+{
+ obstack buf;
+
+ gcc_obstack_init (&buf);
+
+ for (const char *p = format; *p; p++)
+ {
+ switch (*p)
+ {
+ case '%':
+ /* Escape `%' characters so that pp_format does not confuse them
+ for actual format specifiers. */
+ obstack_1grow (&buf, '%');
+ break;
+
+ case '`':
+ /* Escape '`' characters so that expand_d_format does not confuse them
+ for a quoted string. */
+ obstack_1grow (&buf, '\\');
+ break;
+
+ default:
+ break;
+ }
+
+ obstack_1grow (&buf, *p);
+ }
+
+ obstack_1grow (&buf, '\0');
+ return (char *) obstack_finish (&buf);
+}
+
/* Helper routine for all error routines. Reports a diagnostic specified by
KIND at the explicit location LOC. The message FORMAT comes from the dmd
front-end, which does not get translated by the gcc diagnostic routines. */
@@ -177,9 +229,10 @@ verror (const Loc& loc, const char *format, va_list ap,
/* Build string and emit. */
if (prefix2 != NULL)
- xformat = xasprintf ("%s %s %s", prefix1, prefix2, format);
+ xformat = xasprintf ("%s %s %s", escape_d_format (prefix1),
+ escape_d_format (prefix2), format);
else if (prefix1 != NULL)
- xformat = xasprintf ("%s %s", prefix1, format);
+ xformat = xasprintf ("%s %s", escape_d_format (prefix1), format);
else
xformat = xasprintf ("%s", format);
@@ -287,9 +340,10 @@ vdeprecation (const Loc& loc, const char *format, va_list
ap,
/* Build string and emit. */
if (prefix2 != NULL)
- xformat = xasprintf ("%s %s %s", prefix1, prefix2, format);
+ xformat = xasprintf ("%s %s %s", escape_d_format (prefix1),
+ escape_d_format (prefix2), format);
else if (prefix1 != NULL)
- xformat = xasprintf ("%s %s", prefix1, format);
+ xformat = xasprintf ("%s %s", escape_d_format (prefix1), format);
else
xformat = xasprintf ("%s", format);
diff --git a/gcc/testsuite/gdc.dg/pr98457.d b/gcc/testsuite/gdc.dg/pr98457.d
new file mode 100644
index 00000000000..bc0d8af5d4a
--- /dev/null
+++ b/gcc/testsuite/gdc.dg/pr98457.d
@@ -0,0 +1,9 @@
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98457
+// { dg-do compile }
+
+void main()
+{
+ writef!"%s"; // { dg-error "template instance writef!\"%s\" template
.writef. is not defined" }
+ writef!"`%s"; // { dg-error "template instance writef!\"`%s\" template
.writef. is not defined" }
+ writef!"%%s`"; // { dg-error "template instance writef!\"%%s`\" template
.writef. is not defined" }
+}
--
2.27.0
