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jeanpaul zhufenggnss yujincheng08 kiplingw praveenmunagapati houcy brinkqiang pubfork clsptr trmlxz ajunlongliveflexcpp's Issues
Specification example will no longer compile
The specification example given in the flexc++input man page no longer compiles.
Presumably because the mini-scanners are now in a strongly typed enum. Hence if I am not mistaken
"/*" begin(comment);
<comment>.|\n // ignore
<comment>"*/" begin(INITIAL);
needs to become
"/*" begin(StartCondition__::comment);
<comment>.|\n // ignore
<comment>"*/" begin(StartCondition__::INITIAL);
Which is quite ugly, but that is another topic.
Add a function to get column number?
How about adding a function to get the column number of a line? We now have a function to get the line number, how about the column number?
Error building flexcpp with clang
Building flexcpp with clang results in:
./parser/parserbase.h:296:14: error: reference to non-static member function must be called; did you mean to call it with no arguments?
The full log can be found here:
http://clang.debian.net/logs/2016-08-30/flexc++_2.05.00-1_unstable_clang.log
Generated code should be sanitized
Hi,
I created a simple program that uses flexc++ to generate a lexer (along with bisonc++ for a parser), and compiled it with -fsanitize=leak.
I got a memory leak from the lexer code generated by flexc++ :
Direct leak of 280 byte(s) in 1 object(s) allocated from:
#0 0x7f399f313be8 in operator new(unsigned long) (/usr/lib/x86_64-linux-gnu/liblsan.so.0+0xbbe8)
#1 0x4055b1 in ScannerBase::ScannerBase(std::istream&, std::ostream&) ../src/parse/lex.cc:797
It seems that the skeleton file https://github.com/fbb-git/flexcpp/blob/master/flexc%2B%2B/skeletons/flexc%2B%2B.cc does not properly manage the memory for the input/output streams.
Wrong use of [[fallthrough]] attribute in generated .cc
The Lexer implementation generated by flexcpp uses the [[fallthrough]] attribute in a wrong way. It should be followed by a semicolon, see e.g. here and here.
E.g. currently, I have this:
size_t ScannerBase::Input::get()
{
switch(size_t ch = next()) // get the next input char
{
case '\n':
++d_lineNr;
[[fallthrough]]
default:
return ch;
}
}
in my lex.cc, where it should be
size_t ScannerBase::Input::get()
{
switch(size_t ch = next()) // get the next input char
{
case '\n':
++d_lineNr;
[[fallthrough]]; // Semicolon needed!
default:
return ch;
}
}
The Code is thus not conforming to the C++-17 standard. g++ ignores this, but Visual Studio won't compile this Code.
The current man page mentions 1.xx.xx has not been reached
From the current man page:
By now, the project has evolved to a level that we feel it's defensible to publish the program, although we still tend to consider the program in its experimental stage; it will remain that way until we decide to move its version from the 0.9x.xx series to the 1.xx.xx series.
https://github.com/fbb-git/flexcpp/blob/master/flexc%2B%2B/documentation/man/flexc%2B%2B.yo
Since flexc++ is now production ready (right?), this sentence should definitely be replaced.
Problem with nested namespaces
I have problems when using nested namespaces :)
This is my configuration:
%filenames = "MyParser"
%namespace = "my::nested::ns"
%class-name = "MyParser"
%baseclass-header = "MyParserBase.hpp"
%lex-source = "MyParserBase.cpp"
%class-header = "MyParser.hpp"
%implementation-header = "MyParserImpl.hpp"
%%
[ \t]+ // skip white space chars.
[0-9]+ return NUMBER;
[[:alpha:]_][[:alpha:][:digit:]_]* return IDENTIFIER;
[][] return SIGNAL;
. return matched()[0];
\n begin(StartCondition__::INITIAL);
Here is the error:
In file included from parsing/flex/MyParserBase.cpp:9:
In file included from parsing/flex/MyParserImpl.hpp:4:
parsing/flex/MyParser.hpp:3:11: warning: extra tokens at end of #ifndef directive [-Wextra-tokens]
#ifndef my::nested::nsMyParser_H_INCLUDED_
^
//
parsing/flex/MyParser.hpp:4:11: warning: ISO C99 requires whitespace after the macro name [-Wc99-extensions]
#define my::nested::nsMyParser_H_INCLUDED_
^
In file included from parsing/flex/MyParserBase.cpp:9:
In file included from parsing/flex/MyParserImpl.hpp:4:
In file included from parsing/flex/MyParser.hpp:7:
flex/MyParserBase.hpp:3:11: warning: extra tokens at end of #ifndef directive [-Wextra-tokens]
#ifndef my::nested::nsMyParserBASE_H_INCLUDED
^
//
In file included from parsing/flex/MyParserBase.cpp:9:
In file included from parsing/flex/MyParserImpl.hpp:4:
parsing/flex/MyParser.hpp:10:11: error: expected identifier or '{'
namespace my::nested::ns
^
parsing/flex/MyParser.hpp:4:11: note: expanded from macro 'my'
#define my::nested::nsMyParser_H_INCLUDED_
^
parsing/flex/MyParser.hpp:10:11: error: no member named 'nested' in the global namespace
namespace my::nested::ns
^~
parsing/flex/MyParser.hpp:4:13: note: expanded from macro 'my'
#define my::nested::nsMyParser_H_INCLUDED_
~~^
parsing/flex/MyParserBase.cpp:12:11: error: expected identifier or '{'
namespace my::nested::ns
^
parsing/flex/MyParser.hpp:4:11: note: expanded from macro 'my'
#define my::nested::nsMyParser_H_INCLUDED_
^
parsing/flex/MyParserBase.cpp:12:11: error: no member named 'nested' in the global namespace
namespace my::nested::ns
^~
parsing/flex/MyParser.hpp:4:13: note: expanded from macro 'my'
#define my::nested::nsMyParser_H_INCLUDED_
When I replace %namespace = "my::nested::ns" whith %namespace = "mynestedns" everything works as expected. :)
I think that I'm using C++ feature for which flexc++ is not ready yet :)
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