I am trying to use the GNU C library regex functionality in my C++ project, particularly I'm trying to use the regex_t regcomp, regexec, regfree functions. Upon compilation I get errors stating that these symbols are undefined:
me> g++ -I/me/myheaders/ -c RootGenerator.cpp -o RootGenerator.o -std=gnu++0x -Wall
RootGenerator.cpp: In function ‘std::string findFirstFileInCurrentDirectory(std::string)’:
RootGenerator.cpp:1072: error: ‘regex_t’ was not declared in this scope
RootGenerator.cpp:1072: error: expected ‘;’ before ‘re’
RootGenerator.cpp:1073: error: ‘re’ was not declared in this scope
RootGenerator.cpp:1073: error: ‘REG_EXTENDED’ was not declared in this scope
RootGenerator.cpp:1073: error: ‘REG_NOSUB’ was not declared in this scope
RootGenerator.cpp:1073: error: ‘regcomp’ was not declared in this scope
RootGenerator.cpp:1074: error: expected ‘;’ before ‘int’
RootGenerator.cpp:1084: error: ‘status’ was not declared in this scope
RootGenerator.cpp:1084: error: ‘regexec’ was not declared in this scope
RootGenerator.cpp:1092: error: ‘REG_NOMATCH’ was not declared in this scope
RootGenerator.cpp:1108: error: ‘regfree’ was not declared in this scope
I realize that the regex header is a TR1 implementation and is therefore experimental for my version of GCC. I added the -std=gnu++0x compiler option according to the compiler warning recieved when first trying to compile but this doesn't seem to fix the issue. Is this an issue of the system not recognizing and adding paths to "experimental" headers? Are there additional include paths or compiler options that I need to specify?
As an additional note, I noticed in Eclipse/CDT that under the "includes" tab in the Project Explorer view, it shows a list of the system header paths. It lists many header files under the /user/include/c++/4.4.4 path tab, but It doesn't list the regex header. I think this is also reaffirming that there is a setting issue.
Found the problem:
#include <regex>
should be
#include <regex.h>
The regex.h header is the GNU C library implementation of regex, containing the functions I was trying to use in my source. The regex header is the TR1 (and incomplete) regex implemntation. So #Oli, I wasn't referencing the relevant header after all!
Related
I want to use GnuplotHelper in ns3 to plot the results. even when I run ns3's default example seventh.cc I get the following error:
../scratch/congestion.cc: In function ‘int main(int, char**)’:
../scratch/congestion.cc:173:1: error: ‘GnuplotHelper’ was not declared in this scope
GnuplotHelper plotHelper;
^
../scratch/congestion.cc:180:1: error: ‘plotHelper’ was not declared in this scope
plotHelper.ConfigurePlot ("Test","CongestionWindow vs. Time","Time (Seconds)","CongestionWindow","jpg");
^
../scratch/congestion.cc:181:81: error: ‘GnuplotAggregator’ has not been declared
plotHelper.PlotProbe (probeName,probeTrace,"CongetionWindow","CongestionWindow",GnuplotAggregator::KEY_BELOW);
If I include "gnuplot-helper.h" I get an additional line and same error:
../scratch/seventh.cc:24:28: fatal error: gnuplot-helper.h: No such file or directory
compilation terminated.
I've installed gnuplot on my linux. What should I do? How can I declare Gnuplot helper?
First, did you install a gnu-plot-dev package or just gnuplot? Many distributions separate the ability to use libraries and the ability to develop against them.
If you are sure the include files are actually on your system somewhere (check both /usr/include and /usr/local/include/) you may need to add an additional directory level to your compiler search path (perhaps /usr/include/gnuplot/ but I am only guessing there).
Try
#include "ns3/stats-module.h"
I am building a C program with no problem on CentOS using provided Makefiles in its distro package. However I need to modify source files and I need to use iqxmlrpc and boost libraries for that purpose. I have changed Makefiles respectively but when I want to build the package I get following error:
../src/libiqxmlrpc/libiqxmlrpc/except.h:9:21: error: stdexcept: No such file or directory
../src/libiqxmlrpc/libiqxmlrpc/except.h:10:18: error: string: No such file or directory
In file included from ../src/libiqxmlrpc/libiqxmlrpc/libiqxmlrpc.h:17,
from redir.c:2617:
../src/libiqxmlrpc/libiqxmlrpc/except.h:14: error: expected '=', ',', ';', 'asm' or 'attribute' before 'iqxmlrpc'
... followed by many other errors ...
I believe above error is because iqxmlpc is written in c++ and gcc is treating it as C so I tried followings:
1) Use g++
2) Use gcc -x c++
Doing above, error changes to a lot of following in many header files:
error: expected ‘,’ or ‘...’ before ‘this’
All the lines that compiler is complaining somehow have this or delete keywords as parameter. See below:
int net_route(struct in_addr *dst, int delete);
or
extern int gad_new(struct gad_t **this)
Do you have any idea how can I fix this? Frankly, I have no idea what using 'this' or 'delete' mean as parameters. Are these only parameter names that gcc ignores the rule that we can not use keywords?
------------------------------
BTW, original programmer have used nested functions all across his code which were compiled fine using gcc. when I switch to g++, compiler complains about function-definition not being allowed in another function. Is there any way I can tell g++ to ignore this error?
Those weren't keywords in C, they are in C++.
You will have to rename those parameters before the code will compile in C++.
You may run into other porting issues related to C++'s stricter type checking before you are done.
Another option is to keep the C and C++ code in separate files, and use extern "C" in the C++ code for every function call that must cross the boundary. Since your C code extensively uses nested functions and other features not permitted in C++, this is probably your quickest approach.
this and delete are reserved keywords in C++ (not in C though) . You cannot use these as variable names when compiling with g++.
Its better to use different variable names in parameters and then compile with g++.
I am using clang tool to parse standard header file located in /usr/lib/gcc/x86_64-linux-gnu/4.7/string. But I get the following error.
In file included from ~/PrototypeWork/user/header.hpp:3:
In file included from /usr/lib/gcc/x86_64-linux-gnu/4.7/../../../../include/c++/4.7/string:41:
In file included from /usr/lib/gcc/x86_64-linux-gnu/4.7/../../../../include/c++/4.7/bits/char_traits.h:41:
In file included from /usr/lib/gcc/x86_64-linux-gnu/4.7/../../../../include/c++/4.7/bits/postypes.h:41:
/usr/include/c++/4.7/tr1/cwchar:42:14: error: no member named 'wcstof' in namespace 'std'
using std::wcstof;
~~~~~^
/usr/include/c++/4.7/tr1/cwchar:45:14: error: no member named 'vfwscanf' in namespace 'std'
using std::vfwscanf;
~~~~~^
The problem seemed to be that clang is reading string header as a C header instead of c++ header and so it could not parse "using" keyword.
So I went ahead an added the -TP command line options that says to treat all source files as C++ but that did not help.
I get the following warning after using -TP command line option
warning: argument unused during compilation: '-T P'
Can anyone help me with this issue?
Clang command line options: http://clang.llvm.org/docs/UsersManual.html#id5
Code
My main function has these:
int main() {
std::vector<std::string> cmdLine = boost::assign::list_of
("-TP")
("-I/usr/include")
("-I/usr/include/c++/4.7/tr1/");
clang::tooling::FixedCompilationDatabase db(".",cmdLine);
// Provide clang with the header file that needs to be parsed
// Run the clang tool .
}
Sorry if this is a "Thank you, Captain Obvious" answer, but: is it possible that the code being parsed is simply failing to #include <cwchar>? clang is a bit more stringent by default than gcc, so you'll see an error like this if you've failed to include the header that declares the function.
I am developing a program in C++ on Linux. The gcc version is 4.5.1 20100924. I want to use std::atomic_int in my program. I have included atomic header as below:
include <atomic>
When I compile the program I get below errors:
In file included from /usr/lib/gcc/x86_64-redhat-linux/4.5.1/../../../../include/c++/4.5.1/bits/atomic_base.h:87:0,
from /usr/lib/gcc/x86_64-redhat-linux/4.5.1/../../../../include/c++/4.5.1/atomic:41,
from ../Source/Main.h:33:
/usr/lib/gcc/x86_64-redhat-linux/4.5.1/../../../../include/c++/4.5.1/bits/atomicfwd_cxx.h:107:25: error: ‘char16_t’ was not declared in this scope
/usr/lib/gcc/x86_64-redhat-linux/4.5.1/../../../../include/c++/4.5.1/bits/atomicfwd_cxx.h:107:33: error: template argument 1 is invalid
/usr/lib/gcc/x86_64-redhat-linux/4.5.1/../../../../include/c++/4.5.1/bits/atomicfwd_cxx.h:107:53: error: invalid type in declaration before ‘;’ token
/usr/lib/gcc/x86_64-redhat-linux/4.5.1/../../../../include/c++/4.5.1/bits/atomicfwd_cxx.h:110:25: error: ‘char32_t’ was not declared in this scope
/usr/lib/gcc/x86_64-redhat-linux/4.5.1/../../../../include/c++/4.5.1/bits/atomicfwd_cxx.h:110:33: error: template argument 1 is invalid
/usr/lib/gcc/x86_64-redhat-linux/4.5.1/../../../../include/c++/4.5.1/bits/atomicfwd_cxx.h:110:53: error: invalid type in declaration before ‘;’ token
If I include <cstdint>, I get the same errors. The headers uchar.h and cuchar.h are not there on my system. How can I resolve the compilation errors?
Thank you in advance.
EDITED:
I was wrong about that. just pass --std=c++0x to g++, and that would do it.
You seem to not have enabled C++11 support in your compiler or you use a compiler that has these new types not declared.
For char16_t and char32_t, you need no extra include.
g++ howto:
Type g++ --version. If it is at least 4.4, then it has support for new string literals. If not: You need a newer compiler version.
Then, make sure to pass --std=c++0x or --std=c++11 to the compiler.
I'm looking for an implementation of Hybrid Tree(not important), and find an "old" one here.
The author said they have tried this code on the SUN Sparc platform (running Solaris 2.6) and with gcc-2.8.1 compiler. And my environment is gcc version 4.4.3 (Ubuntu 10.10).
The problem is:
I run "make" with the makefile he provides, but it gives me lots of error message as follows:
g++ -c Node.C
g++ -c DataNode.C
In file included from DataNode.h:18,
from DataNode.C:17:
Query.h:9:20: error: vector.h: No such file or directory
Query.h:10:19: error: stack.h: No such file or directory
Query.h:13:22: error: function.h: No such file or directory
Query.h:14:22: error: iostream.h: No such file or directory
DataNode.C:283:8: warning: extra tokens at end of #endif directive
In file included from DataNode.h:18,
from DataNode.C:17:
Query.h:29: warning: ‘typedef’ was ignored in this declaration
Query.h:44: warning: ‘typedef’ was ignored in this declaration
Query.h:86: error: expected initializer before ‘<’ token
Query.h:118: error: ISO C++ forbids declaration of ‘PQ’ with no type
Query.h:118: error: expected ‘;’ before ‘*’ token
Query.h:122: error: ISO C++ forbids declaration of ‘PQ’ with no type
Query.h:122: error: expected ‘;’ before ‘*’ token
Query.h:126: error: ISO C++ forbids declaration of ‘PQ’ with no type
Query.h:126: error: expected ‘;’ before ‘*’ token
Query.h:135: error: expected initializer before ‘<’ token
DataNode.C: In member function ‘void DataNode::DisconnectBranch(int)’:
DataNode.C:80: error: ‘memmove’ was not declared in this scope
make: *** [DataNode.o] Error 1
I know I need to modify the souce code so as to agree with the morden compiler, such as change vector.h to vector. But I find it's just endless.
So my question is: is there any convienent method to run this program, no matter automatically converting this code to "modern-style" or using a standalone "old-style" compiler ?
Any suggestions?
===Update:===
Thank you all, I installed gcc2.8.1 in a different dir using --prefix=/usr/local/gcc-2.8.1 and modify the "makefile" to use this old-version gcc(/usr/local/gcc-2.8.1/bin/gcc). But when I run "make", it still gives me errors of not finding the headers:
/usr/local/gcc-2.8.1/bin/gcc -c DataNode.C
In file included from DataNode.h:18,
from DataNode.C:17:
Query.h:9: vector.h: No such file or directory
Query.h:10: stack.h: No such file or directory
Query.h:11: deque: No such file or directory
Query.h:12: algorithm: No such file or directory
Query.h:13: function.h: No such file or directory
Query.h:14: iostream.h: No such file or directory
make: *** [DataNode.o] Error 1
Then I tried to find these heads in /usr/local/gcc-2.8.1 using find /usr/local/gcc-2.8.1 -name "*vector*", but got nothing.
So where are these heads for the old-version gcc?
You can make a vertor.h yourself which includes vector. This way you can fix the incompatibilities noninvasively.
Edit:
You may also need to add a
using namespace std;
in the header file(s). This is
generally a bad idea but this is one situation where i'd do it anyway.
Once you get it working i would reccomend rewriting it to use the new style header files and namespaces.
Debian Lenny (oldstable) has gcc 3.4. This might have a better backward compatibility. Try to make compatibility headers for the rest of the issues and include them via an extra -I directory, e.g. a vector.h header file that includes vector.
Do yourself the favor and try not to touch the old code. It is easy to break legacy code in unforeseen ways.
You could try running the program on QEMU which supports Solaris 2.6. The only problem might be hunting for the install disc/image. Also, there are people that sells old Solaris boxes on eBay for cheap, you might be able to grab one.
GCC provides download for very old versions, you might be able to get better chance if you try older version of the compiler.
gcc has -fpermissive option: try it and see whether at least some errors disappear. Also: try making a single header file that will include all requisite headers with using directives. For example, make stdinc.h containing:
#include <vector>
#include <iostream>
#include <stack>
...
using std::vector;
using std::fstream;
...
Replace all mentions of legacy C++ header files with a single include of stdinc.h. Old C++ didn't have namespaces, so even if you replace individual directives with just using namespace std;, clashes are unlikely.
If the only thing is
#include <vector.h>
to
#include <vector>
using namespace std;
Why not try sed?
grep for all includes to see if there are other includes than the c++ headers. If not your lucky.
Another thing that is more tricky is that there is old code that relies on accessing data through iterators in a non-standard way. I saw that in a Doom map editor for linux. Then you may need to do manual stuff.