Re: [RFC PATCH 2/2] grep: fallback to interpreter if JIT fails with pcre2
From: Junio C Hamano <hidden>
Date: 2018-12-10 07:00:36
Carlo Marcelo Arenas Belón [off-list ref] writes:
starting with 10.23, and as a side effect of the work for bug1749[1] (grep -P crash with seLinux), pcre2grep was modified to ignore any errors from pcre2_jit_compile so the interpreter could be used as a fallback
That may (or may not---I do not know and I do not particularly feel
the need to know or care about pcre2grep that is somebody else's
project) describe what happened in the pcre2grep project, but it
solicits a "so what?" response without the rest of the sentence you
omitted.
I am guessing that the missing end of the sentence is "we should
follow suit because ...", i.e. something like
Starting from 10.23 [of what??? pcre2grep's version, libpcre's
version, or something else???], pcre2grep falls back to
interpreted pcre when JIT compilation fails. We should follow
suit in "git grep", because ...
quoted hunk
[1] https://bugs.exim.org/show_bug.cgi?id=1749 Signed-off-by: Carlo Marcelo Arenas Belón <redacted> --- grep.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)diff --git a/grep.c b/grep.c index 5ccc0421a1..c751c8cc74 100644 --- a/grep.c +++ b/grep.c@@ -530,8 +530,11 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt pcre2_config(PCRE2_CONFIG_JIT, &p->pcre2_jit_on); if (p->pcre2_jit_on == 1) { jitret = pcre2_jit_compile(p->pcre2_pattern, PCRE2_JIT_COMPLETE); - if (jitret) - die("Couldn't JIT the PCRE2 pattern '%s', got '%d'\n", p->pattern, jitret); + if (jitret) { + /* JIT failed so fallback to the interpreter */ + p->pcre2_jit_on = 0; + return; + } /* * The pcre2_config(PCRE2_CONFIG_JIT, ...) call just