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. 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. --- 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 3bf5a535edd..7043abe10bd 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 != '`') { obstack_1grow (&buf, *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. */ + obstack_1grow (&buf, '`'); + p++;; + } + else + obstack_1grow (&buf, *p); + + p++; + continue; + } + if (*p == '`') { /* Text enclosed by `...` are translated as a quoted string. */ @@ -114,6 +129,43 @@ expand_d_format (const char *format) return (char *) obstack_finish (&buf); } +/* 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); @@ -289,9 +342,10 @@ 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