From: Ulya Trofimovich <skvadrik@gmail.com>
Date: Wed, 25 Mar 2015 16:25:10 +0000 (+0000)
Subject: Fixed bug #57: Wrong result only if another rule is present
X-Git-Tag: 0.14.2~1
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=1a97c678d5ae0dac02234ee65d9bd847dd43c449;p=re2c

Fixed bug #57: Wrong result only if another rule is present

When making regexp alternative, only 'RegExp::PRIVATE' attribute
should be propagated. Propagating 'RegExp::SHARED' attribute is
a mistake, as can be observed from the following example:

    name = "smth1";
    "smth2" | name | "smth3" { ... }
    name                     { ... }

Here, 'name' must have 'RegExp::PRIVATE' attribute, but it gets
broken after alternation. See #bug57 or test 'bug57.re' for full
working example.
---

diff --git a/re2c/actions.cc b/re2c/actions.cc
index 24356cf0..60aba798 100644
--- a/re2c/actions.cc
+++ b/re2c/actions.cc
@@ -278,8 +278,11 @@ RegExp *mkAlt(RegExp *e1, RegExp *e2)
 		m1 = dynamic_cast<MatchOp*>(a->exp1);
 		if (m1 != NULL)
 		{
-			m1->ins_access = e1->ins_access;
-			a->exp2->ins_access = e1->ins_access;
+			if (e1->ins_access == RegExp::PRIVATE)
+			{
+				m1->ins_access = RegExp::PRIVATE;
+				a->exp2->ins_access = RegExp::PRIVATE;
+			}
 			e1 = a->exp2;
 		}
 	}
@@ -296,8 +299,11 @@ RegExp *mkAlt(RegExp *e1, RegExp *e2)
 		m2 = dynamic_cast<MatchOp*>(a->exp1);
 		if (m2 != NULL)
 		{
-			m2->ins_access = e2->ins_access;
-			a->exp2->ins_access = e2->ins_access;
+			if (e2->ins_access == RegExp::PRIVATE)
+			{
+				m2->ins_access = RegExp::PRIVATE;
+				a->exp2->ins_access = RegExp::PRIVATE;
+			}
 			e2 = a->exp2;
 		}
 	}
diff --git a/re2c/test/bug57.c b/re2c/test/bug57.c
new file mode 100644
index 00000000..96f1ce30
--- /dev/null
+++ b/re2c/test/bug57.c
@@ -0,0 +1,114 @@
+/* Generated by re2c */
+#line 1 "bug57.re"
+#include <stdio.h>
+
+int scan(const char *p)
+{
+#define YYCTYPE char
+    const char *YYCURSOR = p;
+    const char *YYMARKER;
+
+
+#line 13 "<stdout>"
+{
+	YYCTYPE yych;
+	unsigned int yyaccept = 0;
+
+	yych = *YYCURSOR;
+	switch (yych) {
+	case '\n':	goto yy2;
+	case '<':	goto yy3;
+	case '\\':	goto yy6;
+	case 'a':	goto yy5;
+	default:	goto yy7;
+	}
+yy2:
+#line 15 "bug57.re"
+	{ return YYCURSOR - p; }
+#line 29 "<stdout>"
+yy3:
+	yyaccept = 0;
+	yych = *(YYMARKER = ++YYCURSOR);
+	switch (yych) {
+	case '>':	goto yy15;
+	case '\\':	goto yy14;
+	case 'x':
+	case 'y':	goto yy12;
+	default:	goto yy4;
+	}
+yy4:
+#line 16 "bug57.re"
+	{ return 0; }
+#line 43 "<stdout>"
+yy5:
+	yyaccept = 1;
+	yych = *(YYMARKER = ++YYCURSOR);
+	goto yy9;
+yy6:
+	yych = *++YYCURSOR;
+	switch (yych) {
+	case 'b':	goto yy8;
+	default:	goto yy4;
+	}
+yy7:
+	yych = *++YYCURSOR;
+	goto yy4;
+yy8:
+	yyaccept = 1;
+	YYMARKER = ++YYCURSOR;
+	yych = *YYCURSOR;
+yy9:
+	switch (yych) {
+	case '\\':	goto yy10;
+	case 'a':	goto yy8;
+	default:	goto yy2;
+	}
+yy10:
+	++YYCURSOR;
+	yych = *YYCURSOR;
+	switch (yych) {
+	case 'b':	goto yy8;
+	default:	goto yy11;
+	}
+yy11:
+	YYCURSOR = YYMARKER;
+	if (yyaccept == 0) {
+		goto yy4;
+	} else {
+		goto yy2;
+	}
+yy12:
+	++YYCURSOR;
+	yych = *YYCURSOR;
+	switch (yych) {
+	case '>':	goto yy15;
+	case '\\':	goto yy14;
+	case 'x':
+	case 'y':	goto yy12;
+	default:	goto yy11;
+	}
+yy14:
+	++YYCURSOR;
+	yych = *YYCURSOR;
+	switch (yych) {
+	case 'b':	goto yy12;
+	default:	goto yy11;
+	}
+yy15:
+	++YYCURSOR;
+#line 14 "bug57.re"
+	{ return YYCURSOR - p; }
+#line 102 "<stdout>"
+}
+#line 17 "bug57.re"
+
+}
+
+int main()
+{
+    const char *str = "aaa\\baaa";
+    int res = scan(str);
+    printf("%d: %s\n", res, str + res);
+    return 0;
+}
+
diff --git a/re2c/test/bug57.re b/re2c/test/bug57.re
new file mode 100644
index 00000000..f50abac3
--- /dev/null
+++ b/re2c/test/bug57.re
@@ -0,0 +1,27 @@
+#include <stdio.h>
+
+int scan(const char *p)
+{
+#define YYCTYPE char
+    const char *YYCURSOR = p;
+    const char *YYMARKER;
+
+/*!re2c
+    re2c:yyfill:enable = 0;
+
+    escaped_char = "\\b";
+
+    [<] ([x] | escaped_char | [y])* [>] { return YYCURSOR - p; }
+    ("a" | escaped_char)* { return YYCURSOR - p; }
+    . { return 0; }
+*/
+}
+
+int main()
+{
+    const char *str = "aaa\\baaa";
+    int res = scan(str);
+    printf("%d: %s\n", res, str + res);
+    return 0;
+}
+