I am using
METEOR#1.4.4.2
WebStorm#2017.1.1
Chrome#58.0.3029.110 (64-bit)
macOS Sierra 10.12.5
ecmascript#0.7.3
ecmascript-runtime#0.3.15
Recently, the debugger started to stop at wrong lines but only visually, mostly it is like 8-14 lines behind the actual breakpoint.
e.g.
*the orange bar indicates the breakpoint in google chrome
console output:
Also, as you can see, some lines are darkened, which means that I can not set a breakpoint there from the browser.
The behavior is the same within the WebStorm internal debugger. So I think it is not Chrome's fault. It looks like the source mapping is broken. I do not know if it is WebStorm, or Meteor that is the cause. Under this conditions it is very hard to debug...
It is difficult to say for sure, but it seems that the issue that you are experiencing is related to a bug that causes Meteor to generate incorrect source maps.
source maps
This is not your browser's "fault". It simply displays the code and the position that is delivered to it by the source maps in your project.
The app.js file and the source map (app.js.map) are generated by the Meteor build process and are served from the .meteor/local/build/programs/web.browser/app directory.
The .map file is responsible of telling the browser how to display the original source, and which segments in the generated app.js file are mapped to which segments in the original source code.
A great explanation about the technical aspects of source maps can be found here.
You can visualize your source maps online and see what maps where using this tool (choose custom... and drag/drop both .js and .map files.
the suspected bug
As a part of the build process, Meteor uses the babel-compiler Meteor package. At some point, a bug caused invalid maps to be produced after babel transformations.
The bug is currently tracked on GitHub and the Meteor folks seem to be closing in on the cause.
what can you do?
At the moment, there is no quick and easy fix.
You can either:
Watch the bug thread and wait for it to be resolved and debug without source maps for now (probably best, if the bug will be fixed soon).
Hack away with local clones of the relevant Meteor packages (could work, I haven't dug into the dependency issues and don't really recommend it, but here's a way of doing it).
Run Meteor from a git checkout in a known good state until a fix is released.
The last option is what #hwilson did in order to begin pinpointing the bug via a git bisect.
You can refer to the Meteor developer document for detailed information regarding the method of running the meteor tool from checkout, but the gist of the things is as follows:
First, make sure that your code, including the .meteor/versions and .meteor/packages are checked out into source control, as you will likely need to mess them up temporarily and will want to restore them once the bug is fixed.
git clone --recursive https://github.com/meteor/meteor.git to a directory of your choosing (e.g, /home/yourname/src/remote.
cd meteor.
git checkout 25a89b5 to get the last known good commit.
git submodule update --init --recursive to make sure everything is still golden after the checkout.
./meteor --help to have the checked out version start
In your project, remove the version info from the .meteor/packages file, as they will likely be incompatible with the ones offered by your checkout.
In your project dir, run /home/yourname/src/remote/meteor/meteor run.
This will run the checked out Meteor version. You may need to do a meteor reset (warning: this clears the local mongo database) or at least clean some of .meteor/local, (e.g, the source maps) for this to work, but this may be unnecessary.
This is quite a lot of effort for a bug which I assume will be resolved in the near future, but I decided to include this info partly in order to be used as documentation for future sourcemap-related issues.
It's hard to say for certain. On a cursory google search it would appear you're not the only one seeing this. As #MasterAM mentioned, it's probably because of source maps from transpilation. I don't think you can do a whole lot about it, but you can try clearing the browser and IDE caches which appears to have worked for some.
Javascript Stops at a line without a breakpoint in remote debug mode
Clearing Webstorm's cache
It is three years too late, but if somebody steel has this problem.
The problem is in the different interpretation of line separators by IDE and compiler, which generates .map files.
For example on the windows in the WebStorm and Angular-Project - the TypeScript compiler ignores line separators, if they are Unix-Style (only LF).
In this case if code formatter transforms too long line to couple of shorter lines and splits these lines by only LF, then in .map file this originally single line will be interpreted as single line, but WebStorm displays by LF separated lines as different lines.
Solution - change line separator to CR+LF and problem will be solved!
P.S. I thin this is a bug in TypeScript compiler
Not sure about this scenario but have faced a similar situation while debugging java with eclipse. It happens when the source code and the compiled/interpreted code that is being debugged - differ.
Try debugging a simple js code to validate if there is something wrong with chrome's js debugger itself. If it works, then an explanation for the lines of code not 'debug-enabled' would be that they are all on the same line (till statement that logs '7'). This could have also offset the line number in the browser.
This is one possible explanation.
I will add that sometimes the Pretty-print of the minified js file add offset in debugging mode between the real line in your code and the shifted line(do to Pretty-print).
So Avoid Pretty-print in mode debug and you will hang to the right line.
Before I begin I must admit that I am new to Xtext and the designing of DSLs. Some of my questions on this matter may be somewhat "less than intelligent".
I have created an Xtext project using the IDE, and I am simultaneously using one of the sample projects provided with Xtext as a guide to what I need to do in my language. I am seeing a lot of warnings that are making me nervous.
Apparently, when the development environment creates a new project, it somehow configures that project to use the Java 5 libraries. I am using Java 6, and as a result I get warnings saying that my project is configured for Java 5 and there is no Java 5 on my system (which there isn't!).
I have tried altering the build path so that it uses Java 6 libraries, but this generates a number of other warnings -- including warnings that the Java 6referenced in my manifest.mf file is invalid!
Then there are the "plugin.xml" warnings. Apparently, the build.properties file references a file called "plugin.xml" which is not created when the IDE creates the project. I have no idea whether or not this file is important enough to create, and I have no idea what should go into it.
Frankly, I hate warnings. Warnings tend to lead to future problems in what I produce. I like clean compiles and clean deployments. I would like to eliminate these warnings, before they start screwing me up down the road (like putting in Java6 classes that would break in a Java5 library).
Has anyone been able to eliminate these warnings reliably? Please advise.
For the JDK warning, you simply switch in the Manifest.MF to a target environment matching your preferred JDK ('JavaSE-1.6 ' in your case).
The warning regarding the missing plugin.xml will be gone as soon as you have run the grammar generator the first time, as it will produce such a file.
Everyone (at least everyone who uses a compiled language) has faced compilation errors but how many times do you get to actually crash the compiler?
I've had my fair share of "internal compiler errors" but most went away just by re-compiling. Do you have a (minimal) piece of code that crashes the compiler?
I write the compiler we use, so it crashes sometimes.
easy.
// -*- C++ -*-
template <int n>
class Foo : public Foo<n+1>
{
};
int main(int, char*[])
{
Foo<0> x;
return 0;
};
ejgottl#luna:~/tmp$ g++ -ftemplate-depth-1000000 -Wall foo.cpp -o foo
g++: Internal error: Segmentation fault (program cc1plus)
Please submit a full bug report.
See `<URL:http://gcc.gnu.org/bugs.html>` for instructions.
For Debian GNU/Linux specific bug reporting instructions, see
`<URL:file:///usr/share/doc/gcc-4.2/README.Bugs>`.
I haven't made GHC (a Haskell compiler) crash yet, but I've gotten it to error out with a
My brain just exploded.
I can't handle pattern bindings for existentially-quantified constructors.
It's pretty easy to work around, and you don't hit this unless you have some tricky (and usually wrong) design, but it probably wins as the best compiler error message ever.
VC catches it gracefully now, but in the mid 90's, this would crashed both Microsoft C++ and Borland C++ compilers:
struct MyClass
{
MyClass operator->() { return *this; }
};
int main(int argc, char* argv[])
{
MyClass A;
A->x;
}
An overloaded operator-> is intrinsically recursive. The function is expected to return a pointer, which oper-> is again applied to. This fragment made code generation infinitely recursive.
Actionscript 3.0:
switch(on_some_variable)
{
}
Empty switch = Kaboom!
Visual C++ 9.0 SP1
this just happened to me
------ Build started: Project: pdfp, Configuration: Debug Win32 ------
Compiling...
reader.cpp
xref.cpp
c:\projects\pdfp\xref.cpp(52) : fatal error C1001: An internal error has occurred in the compiler.
(compiler file 'f:\dd\vctools\compiler\cxxfe\sl\p1\c\toil.c', line 8569)
To work around this problem, try simplifying or changing the program near the locations listed above.
Please choose the Technical Support command on the Visual C++
Help menu, or open the Technical Support help file for more information
Generating Code...
Build log was saved at "file://c:\Projects\pdfp\Debug\BuildLog.htm"
pdfp - 1 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
Well, this didn't actually crash the compiler -- It was merely a bug were VC++ wouldn't accept perfectly good code. (details provided here).
The odd this about it was that it was only triggered when three fairly obscure conditions were all met. Moving one line of code was all that was needed for an effective workaround. And one of the needed pre-conditions was "using namespace std;" which is widely discouraged in production code.
Nevertheless, messages asking how to fix the problem were a staple on Microsoft VC++ newsgroups. I couldn't figure out how so many people stumbled onto an obscure bug. So, eventually, I asked someone.....
The exact code needed to trigger the bug was an example in Stroustrup's "The C++ Programming Langauge". (*)
(*) Note, I'm not saying he did it on purpose. I sure he tested it under a UNIX variant of C++, and was completely unaware of it's affect on VC++.
I've seen a few compiler bugs in the C# compiler (all edge cases, all reported appropriately) and confirmed some crashes provoked by other people.
The scariest compiler (of a sort) bug I've encountered was a JIT bug in one version of Java. It was quite reproducible, but caused the VM to go down. Adding a fairly no-op statement (I can't remember exactly what offhand - possibly just declaring an extra local variable with an initial value) moved it away from whatever corner case it happened to be - and it was fixed in a later version.
This crashed the C64 BASIC:
PRINT 0 + "" +- 0
Yes, especially when it's an old or undermaintained compiler (GCC 2.95, Tendra in C++ mode). I don't keep the pieces of code around, though.
Visual C++ 5. 'Nuff said.
Oops, forgot an 'e' in typedef and crashed the compiler.
typdef struct kGUIColor GameColor;
c:\source\kgui\samples\space\space.cpp(35) : fatal error C1001: INTERNAL COMPILER ERROR
(compiler file 'msc1.cpp', line 2708)
Please choose the Technical Support command on the Visual C++
Help menu, or open the Technical Support help file for more information
Today VS2003SP1 gave me a C1001 (Internal Compiler Error) complaining about compiler file 'msc1.cpp', line 2708) because of this:
struct PATTERN {
…
};
It turns out that the problem was that the structure name I was trying to define (PATTERN) was already a typedef in the GDI for a brush type. However instead of telling me that the symbol is already defined (like it does for most other things) it not only did not point to the structure as the problem—I narrowed the problem down to it by selectively commenting out blocks until the error went away—but it also gave me the aforementioned cryptic error which has nothing to do with the file specified—which I can’t even find to examine the line in question. :|
I was able to reproduce it with the following code:
typedef int SOMETHINGOROTHER;
struct SOMETHINGOROTHER {};
> fatal error C1001: INTERNAL COMPILER ERROR
> (compiler file 'msc1.cpp', line 2708) …
Whereas the following code gives the expected error message:
struct SOMETHINGOROTHER {};
typedef int SOMETHINGOROTHER;
> 'SOMETHINGOROTHER' : redefinition; different basic types
Clearly the problem is in the compiler’s structure handling routine.
I wonder if VS2005+ do better…
Here's a way to crash the VS2003 C++ compiler.
typedef map<int,int> Tmap;
private: Tmap; * m_map;
This will result in a crash and the following error message
fatal error C1001: INTERNAL COMPILER
ERROR (compiler file 'msc1.cpp', line
2708) Please choose the Technical
Support command on the Visual C++ Help
menu, or open the Technical Support
help file for more information
Remove the semicolon immediately after Tmap (second line which defines m_map) to eliminate the error.
In a project I was working in, some specific usages of Boost Lambda expressions could make the Visual C++ compiler crash. (We were using Visual Studio 2003)
The compiler would only crash during the release build, a debug build would work fine.
There had been a religious war raging through the team about the appropriate usage of the lambda libraries, I was almost grateful that the compiler settled it for us. :-)
In version 1.2.x of the Mono C# compiler would crash quite a bit with complicated code (if I remember correctly, nested anonymous delegates). Fortunately with 2.x release, I haven't seen any crashes.
At my previous job we had a simulator which was notorious for being able to crash (ICE) compilers or cause them to generate incorrect code. And when the code actually was generated correctly, ofter the compiler took 15 minutes for a single source file. Visual Studio was never (as long as I worked there) able to compile the simulator core.
The core was automatically generated from a DSL, and the generated code often pushed the compiler to its limits.
Upgrading to a new version of GCC often caused widespread nervosity: will the new version work?
Thanks to #Nick, this crashes VS2005.
template<typename Res, typename T>
Res operator_cast(const T& t)
{
return t.operator Res();
}
int main()
{
return operator_cast<int>(0);
}
I've crashed a compiler before by running it out of memory.
Give a DOS compiler about 0.5mb of source code. Crunch.
When you get a message "Catastrophic Failure" you know you're trying....
Michael
I use both pcc and gcc to compile my old OS project.
I found a bug with how both pcc and gcc handle a non-trivial piece of code and it crashed pcc.
(chars are signed on my platform)
struct{
char myvalue:1;
}mystruct;
pcc crashed because all bitfield values must be int though, so it's really more buggy there, but gcc handles it wrongly. See, if you think about it, it is signed, but only has room for one bit. So therefore, it only can store 0 and -1. Well, gcc handles it wrong by storing 0 or 1.
VC++ has crashed on me when compiling C++ if template usage is messed up (e.g., missing out on a closing ">").
I did. Some Delphi versions (lets say #4) crashed very often with cryptic error messages.
The newer versions (2006 and more) are stable but not rock solid. (7 was great in that case).
Compiler crashes often occur with large edits, and debug sessions of complex projects (lots of dll's). Most of the time a restart of the ide is enough. But sometimes you need to restart the PC.
O and I once crashed OS2 along with the compiler because the swapfile grew too large.
One time when I used the generators example from the Python docs, it broke the version of Python we were using. The same week, one of my colleagues managed to misuse the FFI such that any calculation involving the number 3 would crash python.
The Microsoft Xbox 360 compiler can crash easily. I was given source code with Japanese comments and when converted to regular text one of the last characters on the line was a '\' so it continued the comment onto the next line. If the next line was a switch command, then the compiler crashes.
//wierd japanese characters here %^$$\
switch(n)
{
case 0:
.....
break;
case 1:
.....
break;
}
I have crashed Delphi 7 many times asking it to compile legacy dos code.
The prime culprit seems to be any qualification of something as being in the system unit. This won't always blow it up but when it blows up on such stuff I look through and rewrite anything that requires such an override and the problem goes away.
The blowups are 100% reproduceable but I have never managed to make a simple test case. It doesn't actually crash the compiler most of the time, you usually get an error that has nothing to do with the problem and may be hundreds of lines from it. The environment is destabilized, save and exit is ok but don't think of doing anything else.
Back in the stone age with Borland Pascal 7 (the last dos version) I broke it many times. No crash, just incorrect and inconsistent code emission. I finally learned to keep the .EXE (not counting debug info) below 3mb. The farther beyond that I went the more unstable it got.
I've crashed VC++ a number of times, usually with template code. But that's not the most interesting crash...
I crashed the VS2005 Team System compiler with the /analyze option compiling my shared code library which compiled without error without the switch, and on VS2008 with and without the switch. Of course MS wasn't very interested because it was a bug in the old version of the compiler, but I thought it was pretty interesting.
I managed to segfault the Python interpreter. Of course, I was working on a C extension at the time and getting it not-quite-right.
It doesn't happen as much as it used to, but occasionally the ASP.net precompiler has issues - I haven't seen it personally, but I have fixed a problem on another project once where they had name clashes because they weren't using namespaces properly (caused compiler crashes) during pre-compile.
In the good old days (unmanaged MSVC++) we had the odd compiler crash usually due to linking in external static win32 classes (.lib) and a couple of odd bits of code occasionally caused issues, but these were all picked up very quickly.
I don't know if I would call it crashing, but sdcc (Small Device C Compiler) fails at compiling code formed in a particular way:
Target: 8051
Code had to execute in a 512 byte cache loaded from an external tester
Tester is in control and stores the code - cache can't fetch the next page
No function calls allowed - the PC (program counter) would skip to a place not resident in cache; preprocessor macros were used to accomplish modular coding practice
Jumps (branching) allowed if it doesn't skip out of the cache
No const values - in the data section of the program code which causes code in cache to fetch something not in cache - preprocessor constant (#define) OK here
The preprocessor macros are unrolled resulting in flat, but large code - everything in main(); execution skips the startup code (setting up the stack, etc) and starts at the beginning of main()
Relevant part of this answer:
Occasionally, sdcc would refuse to compile syntactically correct code, with a message about running out of memory. This even happened compiling on 64-bit boxes with 8GB of RAM.
The solution in these cases was to split the firmware into separate pieces and compile them separately and execute them separately. The pieces may have been able to be linked back together, but at that point it didn't matter.
I didn't try it, but the Keil 8051 compiler probably could have handled the problematic code.