From: Nicholas Clark <nick@ccl4.org>
Date: Fri, 2 Feb 2007 14:37:31 +0000 (+0000)
Subject: Change 29502 wasn't perfect - you need to remove any extra trailing
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=610460f93dd5a2665c479dc22acb80489faf9ce7;p=p5sagit%2Fp5-mst-13.2.git

Change 29502 wasn't perfect - you need to remove any extra trailing
"\n" added by fbm_compile(), before recompiling with the same flags.
In turn, to do that, it's best to store the flags even for short
"PVBM"s.

p4raw-id: //depot/perl@30092
---

diff --git a/regexec.c b/regexec.c
index 6c82ba7..8697eb6 100644
--- a/regexec.c
+++ b/regexec.c
@@ -5690,10 +5690,18 @@ S_to_utf8_substr(pTHX_ register regexp *prog)
 	    SV* const sv = newSVsv(prog->substrs->data[i].substr);
 	    prog->substrs->data[i].utf8_substr = sv;
 	    sv_utf8_upgrade(sv);
-	    if (SvVALID(prog->substrs->data[i].substr))
-		fbm_compile(sv, 0);
-	    if (SvTAIL(prog->substrs->data[i].substr))
-		SvTAIL_on(sv);
+	    if (SvVALID(prog->substrs->data[i].substr)) {
+		const U8 flags = BmFLAGS(prog->substrs->data[i].substr);
+		if (flags & FBMcf_TAIL) {
+		    /* Trim the trailing \n that fbm_compile added last
+		       time.  */
+		    SvCUR_set(sv, SvCUR(sv) - 1);
+		    /* Whilst this makes the SV technically "invalid" (as its
+		       buffer is no longer followed by "\0") when fbm_compile()
+		       adds the "\n" back, a "\0" is restored.  */
+		}
+		fbm_compile(sv, flags);
+	    }
 	    if (prog->substrs->data[i].substr == prog->check_substr)
 		prog->check_utf8 = sv;
 	}
@@ -5710,10 +5718,16 @@ S_to_byte_substr(pTHX_ register regexp *prog)
 	    && !prog->substrs->data[i].substr) {
 	    SV* sv = newSVsv(prog->substrs->data[i].utf8_substr);
 	    if (sv_utf8_downgrade(sv, TRUE)) {
-		if (SvVALID(prog->substrs->data[i].utf8_substr))
-		    fbm_compile(sv, 0);
-		if (SvTAIL(prog->substrs->data[i].utf8_substr))
-		    SvTAIL_on(sv);
+		if (SvVALID(prog->substrs->data[i].utf8_substr)) {
+		    const U8 flags
+			= BmFLAGS(prog->substrs->data[i].utf8_substr);
+		    if (flags & FBMcf_TAIL) {
+			/* Trim the trailing \n that fbm_compile added last
+			   time.  */
+			SvCUR_set(sv, SvCUR(sv) - 1);
+		    }
+		    fbm_compile(sv, flags);
+		}	    
 	    } else {
 		SvREFCNT_dec(sv);
 		sv = &PL_sv_undef;
diff --git a/util.c b/util.c
index 1e85eca..a8b83f7 100644
--- a/util.c
+++ b/util.c
@@ -504,7 +504,6 @@ Perl_fbm_compile(pTHX_ SV *sv, U32 flags)
 	    = (unsigned char*)(SvPVX_mutable(sv) + len + PERL_FBM_TABLE_OFFSET);
 	s = table - 1 - PERL_FBM_TABLE_OFFSET;	/* last char */
 	memset((void*)table, mlen, 256);
-	BmFLAGS(sv) = (U8)flags;
 	i = 0;
 	sb = s - mlen + 1;			/* first char (maybe) */
 	while (s >= sb) {
@@ -524,6 +523,7 @@ Perl_fbm_compile(pTHX_ SV *sv, U32 flags)
 	    frequency = PL_freq[s[i]];
 	}
     }
+    BmFLAGS(sv) = (U8)flags;
     BmRARE(sv) = s[rarest];
     BmPREVIOUS(sv) = rarest;
     BmUSEFUL(sv) = 100;			/* Initial value */