Increase PCRE JIT stack size

It is done by implementing the custom stack usage. This makes the
JIT with mode on more compatible with the JIT mode off. Until now, the
default PCRE JIT stack was used which is 32kb big by default. There
are situations where some patterns would fail with JIT while working
correctly without JIT.

The starting size of the JIT stack is still set to 32kb, while the
max is set to the permissive 256kb (and can be increased up to 1mb).
As until now no suchlike bugs regarding JIT were reported, it is expected,
that the stack usage will stay by 32kb in most cases. Though providing
the custom stack, applications will have more room for some sporadic
stack increase, thus more compatibility.

3 files changed, 970 insertions, 2 deletions

diff --git a/ext/pcre/php_pcre.c b/ext/pcre/php_pcre.c
index a522109f3e..128089c0bd 100644
--- a/ext/pcre/php_pcre.c
+++ b/ext/pcre/php_pcre.c
@@ -62,6 +62,11 @@ enum {
 
 PHPAPI ZEND_DECLARE_MODULE_GLOBALS(pcre)
 
+#ifdef PCRE_STUDY_JIT_COMPILE
+#define PCRE_JIT_STACK_MIN_SIZE (32 * 1024)
+#define PCRE_JIT_STACK_MAX_SIZE (256 * 1024)
+ZEND_TLS pcre_jit_stack *jit_stack = NULL;
+#endif
 
 static void pcre_handle_exec_error(int pcre_code) /* {{{ */
 {
@@ -129,6 +134,16 @@ static PHP_GINIT_FUNCTION(pcre) /* {{{ */
 static PHP_GSHUTDOWN_FUNCTION(pcre) /* {{{ */
 {
 	zend_hash_destroy(&pcre_globals->pcre_cache);
+
+#ifdef PCRE_STUDY_JIT_COMPILE
+	/* Stack may only be destroyed when no cached patterns
+	 	possibly associated with it do exist. */
+	if (jit_stack) {
+		pcre_jit_stack_free(jit_stack);
+		jit_stack = NULL;
+	}
+#endif
+
 }
 /* }}} */
 
@@ -197,6 +212,19 @@ static PHP_MSHUTDOWN_FUNCTION(pcre)
 }
 /* }}} */
 
+/* {{{ PHP_RINIT_FUNCTION(pcre) */
+static PHP_RINIT_FUNCTION(pcre)
+{
+#ifdef PCRE_STUDY_JIT_COMPILE
+	if (PCRE_G(jit)) {
+		jit_stack = pcre_jit_stack_alloc(PCRE_JIT_STACK_MIN_SIZE,PCRE_JIT_STACK_MAX_SIZE);
+	}
+#endif
+
+	return SUCCESS;
+}
+/* }}} */
+
 /* {{{ static pcre_clean_cache */
 static int pcre_clean_cache(zval *data, void *arg)
 {
@@ -461,6 +489,11 @@ PHPAPI pcre_cache_entry* pcre_get_compiled_regex_cache(zend_string *regex)
 			extra->flags |= PCRE_EXTRA_MATCH_LIMIT | PCRE_EXTRA_MATCH_LIMIT_RECURSION;
 			extra->match_limit = (unsigned long)PCRE_G(backtrack_limit);
 			extra->match_limit_recursion = (unsigned long)PCRE_G(recursion_limit);
+#ifdef PCRE_STUDY_JIT_COMPILE
+			if (PCRE_G(jit) && jit_stack) {
+				pcre_assign_jit_stack(extra, NULL, jit_stack);
+			}
+#endif
 		}
 		if (error != NULL) {
 			php_error_docref(NULL, E_WARNING, "Error while studying pattern");
@@ -2199,7 +2232,7 @@ zend_module_entry pcre_module_entry = {
 	pcre_functions,
 	PHP_MINIT(pcre),
 	PHP_MSHUTDOWN(pcre),
-	NULL,
+	PHP_RINIT(pcre),
 	NULL,
 	PHP_MINFO(pcre),
 	PHP_PCRE_VERSION,
diff --git a/ext/pcre/tests/preg_match_error3.phpt b/ext/pcre/tests/preg_match_error3.phpt
index 05a9baab07..7202b68b34 100644
--- a/ext/pcre/tests/preg_match_error3.phpt
+++ b/ext/pcre/tests/preg_match_error3.phpt
@@ -2,7 +2,7 @@
 Test preg_match() function : error conditions - jit stacklimit exhausted
 --FILE--
 <?php
-var_dump(preg_match('/^(foo)+$/', str_repeat('foo', 8192)));
+var_dump(preg_match('/^(foo)+$/', str_repeat('foo', 1024*8192)));
 var_dump(preg_last_error() === PREG_JIT_STACKLIMIT_ERROR);
 ?>
 --EXPECT--
diff --git a/ext/pcre/tests/preg_match_error4.phpt b/ext/pcre/tests/preg_match_error4.phpt
new file mode 100644
index 0000000000..06aa82b469
--- /dev/null
+++ b/ext/pcre/tests/preg_match_error4.phpt
@@ -0,0 +1,935 @@
+--TEST--
+Pattern exhausting PCRE JIT stack
+--FILE--
+<?php
+
+$re = '{^(\\s*\\{\\s*(?:"(?:[^\\0-\\x09\\x0a-\\x1f\\\\"]+|\\\\["bfnrt/\\\\]|\\\\u[a-fA-F0-9]{4})*"\\s*:\\s*(?:[0-9.]+|null|true|false|"(?:[^\\0-\\x09\\x0a-\\x1f\\\\"]+|\\\\["bfnrt/\\\\]|\\\\u[a-fA-F0-9]{4})*"|\\[(?:[^\\]]*|\\[(?:[^\\]]*|\\[(?:[^\\]]*|\\[(?:[^\\]]*|\\[[^\\]]*\\])*\\])*\\])*\\]|(?:[^{}]*|\\{(?:[^{}]*|\\{(?:[^{}]*|\\{(?:[^{}]*|\\{[^{}]*\\})*\\})*\\})*\\})*)*\\]|\\{(?:[^{}]*|\\{(?:[^{}]*|\\{(?:[^{}]*|\\{(?:[^{}]*|\\{[^{}]*\\})*\\})*\\})*\\})*\\})\\s*,\\s*)*?)("require"\\s*:\\s*)((?:[0-9.]+|null|true|false|"(?:[^\\0-\\x09\\x0a-\\x1f\\\\"]+|\\\\["bfnrt/\\\\]|\\\\u[a-fA-F0-9]{4})*"|\\[(?:[^\\]]*|\\[(?:[^\\]]*|\\[(?:[^\\]]*|\\[(?:[^\\]]*|\\[[^\\]]*\\])*\\])*\\])*\\]|(?:[^{}]*|\\{(?:[^{}]*|\\{(?:[^{}]*|\\{(?:[^{}]*|\\{[^{}]*\\})*\\})*\\})*\\})*)*\\]|\\{(?:[^{}]*|\\{(?:[^{}]*|\\{(?:[^{}]*|\\{(?:[^{}]*|\\{[^{}]*\\})*\\})*\\})*\\})*\\}))(.*)}s';
+
+$str = '{
+    "config": {
+        "cache-files-ttl": 0,
+        "discard-changes": true
+    },
+    "minimum-stability": "stable",
+    "prefer-stable": false,
+    "provide": {
+        "heroku-sys\\/cedar": "14.2016.03.12"
+    },
+    "repositories": [
+        {
+            "packagist": false
+        },
+        {
+            "type": "path",
+            "url": "\\/tmp\\/buildpacktUY7k\\/support\\/installer\\/",
+            "options": {
+                "symlink": false
+            }
+        },
+        {
+            "type": "composer",
+            "url": "https:\\/\\/lang-php.s3.amazonaws.com\\/dist-cedar-14-stable\\/"
+        },
+        {
+            "type": "package",
+            "package": [
+                {
+                    "type": "metapackage",
+                    "name": "algolia\\/algoliasearch-client-php",
+                    "version": "1.8.1",
+                    "require": {
+                        "heroku-sys\\/ext-mbstring": "*",
+                        "heroku-sys\\/php": ">=5.4"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "algolia\\/algoliasearch-laravel",
+                    "version": "1.0.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "asm89\\/stack-cors",
+                    "version": "0.2.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "aws\\/aws-sdk-php",
+                    "version": "3.15.7",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "aws\\/aws-sdk-php-laravel",
+                    "version": "3.1.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "barryvdh\\/laravel-cors",
+                    "version": "v0.7.3",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "bookingsync\\/oauth2-bookingsync-php",
+                    "version": "0.1.3",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "classpreloader\\/classpreloader",
+                    "version": "3.0.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "danielstjules\\/stringy",
+                    "version": "1.10.0",
+                    "require": {
+                        "heroku-sys\\/ext-mbstring": "*",
+                        "heroku-sys\\/php": ">=5.3.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "dnoegel\\/php-xdg-base-dir",
+                    "version": "0.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "doctrine\\/annotations",
+                    "version": "v1.2.7",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "doctrine\\/cache",
+                    "version": "v1.6.0",
+                    "require": {
+                        "heroku-sys\\/php": "~5.5|~7.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "doctrine\\/collections",
+                    "version": "v1.3.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "doctrine\\/common",
+                    "version": "v2.6.1",
+                    "require": {
+                        "heroku-sys\\/php": "~5.5|~7.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "doctrine\\/dbal",
+                    "version": "v2.5.4",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "doctrine\\/inflector",
+                    "version": "v1.1.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "doctrine\\/lexer",
+                    "version": "v1.0.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "fabpot\\/goutte",
+                    "version": "v3.1.2",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "graham-campbell\\/manager",
+                    "version": "v2.3.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "guzzle\\/guzzle",
+                    "version": "v3.9.3",
+                    "require": {
+                        "heroku-sys\\/ext-curl": "*",
+                        "heroku-sys\\/php": ">=5.3.3"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "guzzlehttp\\/guzzle",
+                    "version": "6.1.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "guzzlehttp\\/promises",
+                    "version": "1.1.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "guzzlehttp\\/psr7",
+                    "version": "1.2.3",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "intercom\\/intercom-php",
+                    "version": "v1.4.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "intervention\\/image",
+                    "version": "2.3.6",
+                    "require": {
+                        "heroku-sys\\/ext-fileinfo": "*",
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "jakub-onderka\\/php-console-color",
+                    "version": "0.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "jakub-onderka\\/php-console-highlighter",
+                    "version": "v0.3.2",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "jeremeamia\\/SuperClosure",
+                    "version": "2.2.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "jlapp\\/swaggervel",
+                    "version": "dev-master",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "laravel\\/framework",
+                    "version": "v5.1.31",
+                    "require": {
+                        "heroku-sys\\/ext-mbstring": "*",
+                        "heroku-sys\\/ext-openssl": "*",
+                        "heroku-sys\\/php": ">=5.5.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "laravelcollective\\/html",
+                    "version": "v5.1.9",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "league\\/flysystem",
+                    "version": "1.0.18",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "league\\/flysystem-aws-s3-v3",
+                    "version": "1.0.9",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "league\\/fractal",
+                    "version": "0.13.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "league\\/glide",
+                    "version": "1.0.0",
+                    "require": {
+                        "heroku-sys\\/php": "^5.4 | ^7.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "league\\/oauth2-client",
+                    "version": "0.12.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "mindscape\\/raygun4php",
+                    "version": "dev-master",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "monolog\\/monolog",
+                    "version": "1.18.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "mtdowling\\/cron-expression",
+                    "version": "v1.1.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "mtdowling\\/jmespath.php",
+                    "version": "2.3.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "namshi\\/jose",
+                    "version": "5.0.2",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.3"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "nesbot\\/carbon",
+                    "version": "1.21.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "nikic\\/php-parser",
+                    "version": "v2.0.1",
+                    "require": {
+                        "heroku-sys\\/ext-tokenizer": "*",
+                        "heroku-sys\\/php": ">=5.4"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "orangehill\\/iseed",
+                    "version": "dev-master",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "paragonie\\/random_compat",
+                    "version": "v1.2.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.2.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "phpseclib\\/phpseclib",
+                    "version": "0.3.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.0.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "predis\\/predis",
+                    "version": "v1.0.3",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "psr\\/http-message",
+                    "version": "1.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "psy\\/psysh",
+                    "version": "v0.7.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "swiftmailer\\/swiftmailer",
+                    "version": "v5.4.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.3"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/browser-kit",
+                    "version": "v2.8.3",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/console",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/css-selector",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/debug",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/dom-crawler",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/event-dispatcher",
+                    "version": "v2.8.3",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/finder",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/http-foundation",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/http-kernel",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/polyfill-php56",
+                    "version": "v1.1.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.3"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/polyfill-util",
+                    "version": "v1.1.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.3"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/process",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/routing",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/translation",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "symfony\\/var-dumper",
+                    "version": "v2.7.10",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.9"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "twilio\\/sdk",
+                    "version": "4.10.0",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.2.1"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "tymon\\/jwt-auth",
+                    "version": "0.5.9",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "vinkla\\/algolia",
+                    "version": "2.2.1",
+                    "require": {
+                        "heroku-sys\\/php": "^5.5.9 || ^7.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "vlucas\\/phpdotenv",
+                    "version": "v1.1.1",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.3.2"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "zircote\\/swagger-php",
+                    "version": "2.0.6",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.4.0"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                },
+                {
+                    "type": "metapackage",
+                    "name": "composer.json\\/composer.lock",
+                    "version": "dev-a923f6cdbbc9439cabb74aa9003f6d51",
+                    "require": {
+                        "heroku-sys\\/php": ">=5.5.9",
+                        "heroku-sys\\/ext-gd": "*",
+                        "heroku-sys\\/ext-exif": "*",
+                        "heroku-sys\\/ext-fileinfo": "*"
+                    },
+                    "replace": [],
+                    "provide": [],
+                    "conflict": []
+                }
+            ]
+        }
+    ],
+    "require": {
+        "composer.json\\/composer.lock": "dev-a923f6cdbbc9439cabb74aa9003f6d51",
+        "algolia\\/algoliasearch-client-php": "1.8.1",
+        "algolia\\/algoliasearch-laravel": "1.0.10",
+        "asm89\\/stack-cors": "0.2.1",
+        "aws\\/aws-sdk-php": "3.15.7",
+        "aws\\/aws-sdk-php-laravel": "3.1.0",
+        "barryvdh\\/laravel-cors": "v0.7.3",
+        "bookingsync\\/oauth2-bookingsync-php": "0.1.3",
+        "classpreloader\\/classpreloader": "3.0.0",
+        "danielstjules\\/stringy": "1.10.0",
+        "dnoegel\\/php-xdg-base-dir": "0.1",
+        "doctrine\\/annotations": "v1.2.7",
+        "doctrine\\/cache": "v1.6.0",
+        "doctrine\\/collections": "v1.3.0",
+        "doctrine\\/common": "v2.6.1",
+        "doctrine\\/dbal": "v2.5.4",
+        "doctrine\\/inflector": "v1.1.0",
+        "doctrine\\/lexer": "v1.0.1",
+        "fabpot\\/goutte": "v3.1.2",
+        "graham-campbell\\/manager": "v2.3.1",
+        "guzzle\\/guzzle": "v3.9.3",
+        "guzzlehttp\\/guzzle": "6.1.1",
+        "guzzlehttp\\/promises": "1.1.0",
+        "guzzlehttp\\/psr7": "1.2.3",
+        "intercom\\/intercom-php": "v1.4.0",
+        "intervention\\/image": "2.3.6",
+        "jakub-onderka\\/php-console-color": "0.1",
+        "jakub-onderka\\/php-console-highlighter": "v0.3.2",
+        "jeremeamia\\/SuperClosure": "2.2.0",
+        "jlapp\\/swaggervel": "dev-master",
+        "laravel\\/framework": "v5.1.31",
+        "laravelcollective\\/html": "v5.1.9",
+        "league\\/flysystem": "1.0.18",
+        "league\\/flysystem-aws-s3-v3": "1.0.9",
+        "league\\/fractal": "0.13.0",
+        "league\\/glide": "1.0.0",
+        "league\\/oauth2-client": "0.12.1",
+        "mindscape\\/raygun4php": "dev-master",
+        "monolog\\/monolog": "1.18.0",
+        "mtdowling\\/cron-expression": "v1.1.0",
+        "mtdowling\\/jmespath.php": "2.3.0",
+        "namshi\\/jose": "5.0.2",
+        "nesbot\\/carbon": "1.21.0",
+        "nikic\\/php-parser": "v2.0.1",
+        "orangehill\\/iseed": "dev-master",
+        "paragonie\\/random_compat": "v1.2.1",
+        "phpseclib\\/phpseclib": "0.3.10",
+        "predis\\/predis": "v1.0.3",
+        "psr\\/http-message": "1.0",
+        "psy\\/psysh": "v0.7.1",
+        "swiftmailer\\/swiftmailer": "v5.4.1",
+        "symfony\\/browser-kit": "v2.8.3",
+        "symfony\\/console": "v2.7.10",
+        "symfony\\/css-selector": "v2.7.10",
+        "symfony\\/debug": "v2.7.10",
+        "symfony\\/dom-crawler": "v2.7.10",
+        "symfony\\/event-dispatcher": "v2.8.3",
+        "symfony\\/finder": "v2.7.10",
+        "symfony\\/http-foundation": "v2.7.10",
+        "symfony\\/http-kernel": "v2.7.10",
+        "symfony\\/polyfill-php56": "v1.1.0",
+        "symfony\\/polyfill-util": "v1.1.0",
+        "symfony\\/process": "v2.7.10",
+        "symfony\\/routing": "v2.7.10",
+        "symfony\\/translation": "v2.7.10",
+        "symfony\\/var-dumper": "v2.7.10",
+        "twilio\\/sdk": "4.10.0",
+        "tymon\\/jwt-auth": "0.5.9",
+        "vinkla\\/algolia": "2.2.1",
+        "vlucas\\/phpdotenv": "v1.1.1",
+        "zircote\\/swagger-php": "2.0.6",
+        "heroku-sys\\/apache": "^2.4.10",
+        "heroku-sys\\/nginx": "~1.8.0"
+    }
+}';
+
+$count = preg_match($re, $str, $matches);
+
+if($count === false) {
+    switch (preg_last_error()) {
+        case PREG_NO_ERROR:
+            throw new \RuntimeException('Failed to execute regex: PREG_NO_ERROR', PREG_NO_ERROR);
+        case PREG_INTERNAL_ERROR:
+            throw new \RuntimeException('Failed to execute regex: PREG_INTERNAL_ERROR', PREG_INTERNAL_ERROR);
+        case PREG_BACKTRACK_LIMIT_ERROR:
+            throw new \RuntimeException('Failed to execute regex: PREG_BACKTRACK_LIMIT_ERROR', PREG_BACKTRACK_LIMIT_ERROR);
+        case PREG_RECURSION_LIMIT_ERROR:
+            throw new \RuntimeException('Failed to execute regex: PREG_RECURSION_LIMIT_ERROR', PREG_RECURSION_LIMIT_ERROR);
+        case PREG_BAD_UTF8_ERROR:
+            throw new \RuntimeException('Failed to execute regex: PREG_BAD_UTF8_ERROR', PREG_BAD_UTF8_ERROR);
+        case PREG_BAD_UTF8_OFFSET_ERROR:
+            throw new \RuntimeException('Failed to execute regex: PREG_BAD_UTF8_OFFSET_ERROR', PREG_BAD_UTF8_OFFSET_ERROR);
+        case PREG_JIT_STACKLIMIT_ERROR:
+            throw new \RuntimeException('Failed to execute regex: PREG_JIT_STACKLIMIT_ERROR', PREG_JIT_STACKLIMIT_ERROR);
+        default:
+            throw new \RuntimeException('Failed to execute regex: Unknown error');
+    }
+} else {
+	var_dump("Done, $count matches.");
+}
+?>
+==DONE==
+--EXPECT--
+string(16) "Done, 1 matches."
+==DONE==