Description:
------------
running php 7(7.1.13) using php-cgi on lighttpd causes segmentation fault at zend_ast.h.

the segmentation fault is:
php-cgi[8722]: unhandled signal 11 at 68700050 nip 1029b9c8 lr 1029e4c0 code 30

gdb info is:
(gdb) list *0x1029b9c8
0x1029b9c8 is in zend_compile_expr (Zend/zend_sst.h:239).
234  static zend_always_inline uint32_t zend_ast_get_num_children(zend_ast *ast) {
235	ZEND_ASSERT(!zend_ast_is_list(ast));
236	return ast->kind >> ZEND_AST_NUM_CHILDREN_SHIFT;
237 }
238  static zend_always_inline uint32_t zend_ast_get_lineno(zend_ast *ast) {
239	if (ast->kind == ZEND_AST_ZVAL) {
240		zval *zv = zend_ast_get_zval(ast);
241		return zv->u2.lineno;
242	} else {
243		return ast->lineno;
244	}

php 5.6.33 running ok.

Test script:
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<? phpinfo(); ?>

Expected result:
----------------
show phpinfo page

Actual result:
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500 - Internal Server Error