Mac Stringstream returns wrong output
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@Bugi said in Mac Stringstream returns wrong output:
I don't think there are many opportunities to change the compiler on macOS.
I think Python is the same way on MacOS.
Can you add an independent compiler? One that you can run from the command line? Not one that changes the entire system compiler. My Linux system has a standard gcc compiler installed, but I can install clang and it won't mess up everything else. That would at least give you a way to do your school work.
I still think the VM option with Linux on it may be your best option. I know you don't want to, but it will give you a lot more options. It will also give you experience in Linux if you don't already have that.
wrote on 31 May 2019, 21:49 last edited by@fcarney
Agree and have begun to take baby steps with linux (ubunto).
I was dedcated windows user some years ago (before windows 8) and have worked on windows machines afterwards continued.
regarding my school work i have found a windows machine for the moment.
BUT. I am still detement to make it work on mac os. I'm really tired of hearing people say you can't be an engineer with a mac.and I'm really happy with my mac :(
And although I have a windows machine it doesn't help the others in my class with the same problem (mac user) -
wrote on 31 May 2019, 21:57 last edited by
@Bugi said in Mac Stringstream returns wrong output:
I'm really tired of hearing people say you can't be an engineer with a mac.
The guy I share an office with is an electrical engineer (30+ years), he is a good programmer, uses a Mac, but runs most of his analysis software and programming tools on a VM running Windows 10. I run Linux and use a VM to run Windows 10 for doing Windows development in Qt. Most of my time is in Linux though. So, there is nothing wrong with a Mac. However, no matter what you run, you will probably need a VM to run something else. Or your boss will make a decision that forces you to run a VM. Its just how it goes.
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Okay maybe we found something here ...
but since I still have very little code experience I don't know if it is something or not... Or for that matter what it means
Output:ios_base::clear: unspecified iostream_category error libc++abi.dylib: terminating with uncaught exception of type std::__1::ios_base::failure: ios_base::clear: unspecified iostream_category error Press <RETURN> to close this window...It went directly to line 49: (throw) after line 39: (ss >> coeff;)
Se folder and Debug_4 for code and images.@Bugi said in Mac Stringstream returns wrong output:
Okay maybe we found something here ...
but since I still have very little code experience I don't know if it is something or not... Or for that matter what it meansIt means one of two things:
- You're reading past the end of stream.
- You're reading formatted input (the
>>operators), which is not formatted according to the expectation; i.e. there's something wrong while reading from the stream.
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wrote on 2 Jun 2019, 00:42 last edited by
just for grins...please replace std:stringtream with std::istringstream and retest. Since you are only using the stream for input, you should use the istream specialization intended for that purpose.
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Okay maybe we found something here ...
but since I still have very little code experience I don't know if it is something or not... Or for that matter what it means
Output:ios_base::clear: unspecified iostream_category error libc++abi.dylib: terminating with uncaught exception of type std::__1::ios_base::failure: ios_base::clear: unspecified iostream_category error Press <RETURN> to close this window...It went directly to line 49: (throw) after line 39: (ss >> coeff;)
Se folder and Debug_4 for code and images.@Bugi said in Mac Stringstream returns wrong output:
ios_base::clear: unspecified iostream_category error libc++abi.dylib: terminating with uncaught exception of type std::__1::ios_base::failure: ios_base::clear: unspecified iostream_category errorSomeone found a bug in clang's stringstream exception detection before (http://clang-developers.42468.n3.nabble.com/libc-ios-base-and-exceptions-td4038960.html ); it's quite possible that your compiler has a buggy implementation of stringstream. This would explain why everyone on this forum was unable to reproduce your issue, yet all 6 macOS users in your class have the same issue.
Unless you have a way to try a different compiler on your macOS, you'll have a hard time proving or disproving that the bug is in your compiler.
Does this exercise require you to use stringstream? If not, try a different way of parsing the string.
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@Bugi said in Mac Stringstream returns wrong output:
ios_base::clear: unspecified iostream_category error libc++abi.dylib: terminating with uncaught exception of type std::__1::ios_base::failure: ios_base::clear: unspecified iostream_category errorSomeone found a bug in clang's stringstream exception detection before (http://clang-developers.42468.n3.nabble.com/libc-ios-base-and-exceptions-td4038960.html ); it's quite possible that your compiler has a buggy implementation of stringstream. This would explain why everyone on this forum was unable to reproduce your issue, yet all 6 macOS users in your class have the same issue.
Unless you have a way to try a different compiler on your macOS, you'll have a hard time proving or disproving that the bug is in your compiler.
Does this exercise require you to use stringstream? If not, try a different way of parsing the string.
Anyway, in situations like this, it is useful to create minimal test cases to investigate the issue.
int main() { std::string pstr = "22x^3+2x^2-1x^0"; std::stringstream ss(pstr); double coeff = -42.0; ss >> coeff; std::cout << coeff << std::endl; }What does this print for you? If it's the wrong value, what happens if you replace pstr with "22"?
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@Bugi said in Mac Stringstream returns wrong output:
ios_base::clear: unspecified iostream_category error libc++abi.dylib: terminating with uncaught exception of type std::__1::ios_base::failure: ios_base::clear: unspecified iostream_category errorSomeone found a bug in clang's stringstream exception detection before (http://clang-developers.42468.n3.nabble.com/libc-ios-base-and-exceptions-td4038960.html ); it's quite possible that your compiler has a buggy implementation of stringstream. This would explain why everyone on this forum was unable to reproduce your issue, yet all 6 macOS users in your class have the same issue.
Unless you have a way to try a different compiler on your macOS, you'll have a hard time proving or disproving that the bug is in your compiler.
Does this exercise require you to use stringstream? If not, try a different way of parsing the string.
wrote on 2 Jun 2019, 19:35 last edited by@JKSH said in Mac Stringstream returns wrong output:
Unless you have a way to try a different compiler on your macOS, you'll have a hard time proving or disproving that the bug is in your compiler.
However, it would be wise to update Xcode to the latest available version before investigating further
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Hi we are two students in my class who has a slightly strange experience with string stream on our Qt installation C++
Common trails of setup:
- macOS Majave v. 10.14
- Qt Creator 4.9.1
- Kit: Desktop Qt 5.12.2 clang 64bit (default)
Our Code C++: main.cpp
/#include <iostream> #include <sstream> #include <vector> #include <utility> std::vector<std::pair<double, int> > readPolynomial(std::string& p); int main() { std::string pstr = "22x^3+2x^2-1x^0"; std::vector<std::pair<double, int> > poly = readPolynomial(pstr); for (unsigned int i = 0; i < poly.size(); ++i) { if (i>0) { if (poly[i].first > 0) { std::cout << "+"; } } std::cout << poly[i].first << "x^" << poly[i].second; } std::cout << std::endl; return 0; } std::vector<std::pair<double, int> > readPolynomial(std::string& p) { std::vector<std::pair<double, int> > poly(3); std::stringstream stringstream(p); for (size_t i{0}; i < 3; i++) { stringstream >> poly[i].first; stringstream.ignore(2); stringstream >> poly[i].second; } return poly; }Output: Terminal
0x^00x^00x^0Any suggestions?
PS. please be detailed we are first year and new to Qt, C ++, and Terminal commandUpdate 1:
Im not he best at using the debugging tool.
but at the following link you can fine some pictures of the debugging window.
link debugging Images -
wrote on 16 Jun 2019, 09:32 last edited by wraitii
I've ran in the same problem in 0 A.D. (see here).
Edit: this is in fact a difference between libstd and libc and it has been reported before: https://bugs.llvm.org/show_bug.cgi?id=17782
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I've ran in the same problem in 0 A.D. (see here).
Edit: this is in fact a difference between libstd and libc and it has been reported before: https://bugs.llvm.org/show_bug.cgi?id=17782
wrote on 16 Jun 2019, 10:05 last edited by Konstantin Tokarev@wraitii Thanks for information! You've probably meant libstdc++ and libc++, because libc is kinda different thing