Mac List Symbols In Static Library
Dec 01, 2016 The iOS app links to a static library (a FAT lib, i.e all architectures) which seems to be written in C. So the external library has a libSomething.a and a libSomething.h file. The source code of the original iOS app has a.mm file which references the 'libSomething.h' and calls the various methods and functions within the static library. Contribute to microsoft/WinObjC development by creating an account on GitHub. Creating and Linking Against C Static Libraries. Jump to bottom. Follow the instructions below to have your Objective-C application project link against a C static library. Creating C Static Libraries. In Visual Studio. I'm coding an static library and there is a one class. But I don't understand why all the member variables and methods (all variables are private) are visible in generated lib file. Even the paths and project command line can be found there. As-well there is a lot other 'unneeded' information. I moved this line to the end of.pro file and now I can compile and link with my Fortran static library with no errors! This solved my problem!. but I also wanted you to list the symbols from the libgfortran in your path and grep against one of the missing symbols, say gfortrandateandtime. In the library.a folder I typed. Mar 21, 2014 When the linker adds functions to an image, it makes note of the sticker and adds it to the list of functions that it needs to export. But if the linker never sees the function, then it never sees the sticker. In order to export a function from a static library, you need to.
- Mac List Symbols In Static Library In History
- Mac List Symbols In Static Library In India
- Mac Keyboard Symbols List
- Mac List Symbols In Static Library In Java
- Symbols On A Mac
- Mac List Symbols In Static Library In Windows 10
by Angel Leon. March 17, 2015; August 29, 2019.
Include Paths
Sep 18, 2013 The tables in this chapter list commonly used GDB commands and present equivalent LLDB commands and alternative forms. Also listed are the built-in GDB compatibility aliases in LLDB. Notice that full LLDB command names can be matched by unique short forms, which can be used instead.
On the compilation phase, you will usually need to specify the different include paths so that the interfaces (.h, .hpp) which define structs, classes, constans, and functions can be found.
With gcc and llvm include paths are passed with -I/path/to/includes, you can pass as many -I as you need.
In Windows, cl.exe takes include paths with the following syntax:/I'c:pathtoincludes you can also pass as many as you need.
Some software uses macro definition variables that should be passed during compile time to decide what code to include.
Compilation flags
These compilation-time variables are passed using -D,e.g. -DMYSOFTWARE_COMPILATION_VARIABLE-DDO_SOMETHING=1-DDISABLE_DEPRECATED_FUNCTIONS=0
These compilation time flags are by convention usually put into a single variable named CXXFLAGS, which is then passed to the compiler as a parameter for convenience when you're building your compilation/make script.
Object files
When you compile your .c, or .cpp files, you will end up with object files.These files usually have .o extensions in Linux, in Windows they might be under .obj extensions.
You can create an .o file for a single or for many source files.
Static Library files
When you have several .o files, you can put them together as a library, a static library. In Linux/Mac these static libraries are simply archive files, or .a files. In windows, static library files exist under the .lib extension.
They are created like this in Linux/Mac:
ar -cvq libctest.a ctest1.o ctest2.o ctest3.o
libctest.a will contain ctest1.o,ctest2.o and ctest2.o
They are created like this in Windows:
LIB.EXE /OUT:MYLIB.LIB FILE1.OBJ FILE2.OBJ FILE3.OBJ
When you are creating an executable that needs to make use of a library, if you use these static libraries, the size of your executable will be the sum of all the object files statically linked by the executable. The code is right there along the executable, it's easier to distribute, but again, the size of the executable can be bigger than it needs to.. why? because, sometimes, many of the .o files, or even the entire .a file you're linking against might be a standard library that many other programs need.
Shared Libraries (Dynamic Libraries)
So shared or dynamic libraries were invented so that different programs or libraries would make external (shared) references to them, since they're 'shared' the symbols defined in them don't need to be part of your executable or library, your executable contain symbols whose entry points or offset addresses might point to somewhere within themselves, but they will also have symbols whose entry points are expected to exist on shared libraries which need only be loaded once in a single portion of the operating shared memory, thus not just making the size of your executable as small as it needs to be, but you won't need to load the library for every process/program that needs its symbols.
On Linux shared files exist under the .so (shared object) file extension, on Mac .dylib (dynamic library), and in Windows they're called .dll (dynamic link libraries)
Another cool thing about dynamic libraries, is that they can be loaded during runtime, not just linked at compile time. An example of runtime dynamic libraries are browser plugins.
In Linux .so files are created like this:
-Wallenables all warnings.-cmeans compile only, don't run the linker.-fPICmeans 'Position Independent Code', a requirement for shared libraries in Linux.-sharedmakes the object file created shareable by different executables.-Wlpasses a comma separated list of arguments to the linker.-sonamemeans 'shared object name' to use.-o <my.so>means output, in this case the output shared library
In Mac .dylib files are created like this:
clang -dynamiclib -o libtest.dylib file1.o file2.o -L/some/library/path -lname_of_library_without_lib_prefix
In Windows .dll files are created like this:
LINK.EXE /DLL /OUT:MYLIB.DLL FILE1.OBJ FILE2.OBJ FILE3OBJ
Linking to existing libraries
When linking your software you may be faced with a situation on which you want to link against several standard shared libraries.If all the libraries you need exist in a single folder, you can set the LD_LIBRARY_PATH to that folder. By common standard all shared libraries are prefixed with the word lib. If a library exists in LD_LIBRARY_PATH and you want to link against it, you don't need to pass the entire path to the library, you simply pass -lname and you will link your executable to the symbols of libname.so which should be somewhere inside LD_LIBRARY_PATH.
Tip: You should probably stay away from altering your LD_LIBRARY_PATH, if you do, make sure you keep its original value, and when you're done restore it, as you might screw the build processes of other software in the system which might depend on what's on the LD_LIBRARY_PATH.
What if libraries are in different folders?
If you have some other libbar.so library on another folder outside LD_LIBRARY_PATH you can explictly pass the full path to that library /path/to/that/other/library/libbar.so, or you can specify the folder that contains it -L/path/to/that/other/library and then the short hand form -lbar. This latter option makes more sense if the second folder contains several other libraries.
Useful tools
Sometimes you may be dealing with issues like undefined symbol errors, and you may want to inspect what symbols (functions) are defined in your library.
Mac List Symbols In Static Library In History
On Mac there's otool, on Linux/Mac there's nm, on Windows there's depends.exe (a GUI tool that can be used to see both dependencies and the symbol's tables. Taking a look at the 'Entry Point' column will help you understand clearly the difference between symbols linking to a shared library vs symbols linking statically to the same library)
Useful command options
See shared library dependencies on Mac with otool
See shared symbols with nm (Linux/Mac)With nm, you can see the symbol's name list.Familiarize yourself with the meaning of the symbol types:
T(text section symbol)U(undefined - useful for thoseundefined symbolerror),I(indirect symbol).
If the symbol is local (non-external) the symbol type is presented in lowercase letters, for example a lowercase u represents an undefined reference to a private external in another module in the same library.
nm's documentation says that if you're working on Mac and you see that the symbol is preceeded by + or - it means it's an ObjectiveC method, if you're familiar with ObjectiveC you will know that + is for class methods and - is for instance methods, but in practice it seems to be a bit more explicit and you will often see objc or OBJC prefixed to those methods.
nm is best used along with grep ;)
Find all Undefined symbols
My C++ code compiles but it won't link
Linking is simply 'linking' a bunch of .o files to make an executable.
Each one of these .o's may be compiled on their own out of their .cpp files, but when one references symbols that are supposed to exist in other .o's and they're not to be found then you get linking errors.
Perhaps through forward declarations you managed your compilation phase to pass, but then you get a bunch of symbol not found errors.Make sure to read them slowly, see where these symbols are being referenced, you will see that these issues occur due to namespace visibility in most cases.
Perhaps you copied the signature of a method that exists in a private space elsewhere into some other namespace where your code wasn't compiling, all you did was make it compilable, but the actual symbol might not be visible outside the scope where it's truly defined and implemented.
Function symbols can be private if they're declared inside anonymous namespaces, or if they're declared as static functions.
An example:
Here, when I read the code of Network::TxMessage::handle(..) there was a call to FlushStateToDisk, which was declared in main.h, and coded in main.cpp. My TxMessage.cpp did include main.h, compilation was fine, I had a TxMessage.o file and a main.o, but the linker was complaining.
The issue was that FlushStateToDisk was declared as a static, therefore only visible inside main.o, once I removed the static from the declaration and implementation the error went away and my executable was linked. Similar things happen when functions are declared in anonymous spaces in other files, even if you forward declare them on your local .h
In other cases your code compiles and you get this error linking because your library can't be added using -lfoo, and adding its containing folder to -L doesn't cut it, in this case you just add the full path to the library in your compilation command: gcc /path/to/the/missing/library.o .. my_source.cpp -o my_executable
Reminder:
DO NOT EXPORT CFLAGS, CPPFLAGS and the like on your .bash_profile/.bashrc, it can lead to unintended building consequences in many projects. I've wasted so many hours due to this mistake.
The tables in this chapter list commonly used GDB commands and present equivalent LLDB commands and alternative forms. Also listed are the built-in GDB compatibility aliases in LLDB.
Notice that full LLDB command names can be matched by unique short forms, which can be used instead. For example, instead of breakpoint set, br se can be used.
Execution Commands
GDB | LLDB |
|---|---|
Launch a process with no arguments. | |
|
|
Launch a process with arguments | |
|
|
Launch process | |
|
|
Launch a process with arguments in a new terminal window (OS X only). | |
— |
|
Launch a process with arguments in an existing Terminal window, | |
— |
|
Set environment variables for process before launching. | |
|
|
Set environment variables for process and launch process in one command. | |
| |
Attach to the process with process ID 123. | |
|
|
Attach to a process named | |
|
|
Wait for a process named | |
|
|
Attach to a remote GDB protocol server running on the system | |
|
|
Attach to a remote GDB protocol server running on the local system, port 8000. | |
|
|
Attach to a Darwin kernel in kdp mode on the system | |
|
|
Do a source-level single step in the currently selected thread. | |
|
|
Do a source-level single step over in the currently selected thread. | |
|
|
Do an instruction-level single step in the currently selected thread. | |
|
|
Do an instruction-level single step over in the currently selected thread. | |
|
|
Step out of the currently selected frame. | |
|
|
Backtrace and disassemble every time you stop. | |
— |
|
Breakpoint Commands
GDB | LLDB |
|---|---|
Set a breakpoint at all functions named | |
|
|
Set a breakpoint in file | |
|
|
Set a breakpoint at all C++ methods whose basename is | |
(Note: This will break on any C functions named |
|
Set a breakpoint at an Objective-C function: | |
|
|
Set a breakpoint at all Objective-C methods whose selector is | |
(Note: This will break on any C or C++ functions named |
|
Set a breakpoint by a regular expression on a function name. | |
|
|
Set a breakpoint by a regular expression on a source file’s contents. | |
|
|
List all breakpoints. | |
|
|
Delete a breakpoint. | |
|
|
Watchpoint Commands
GDB | LLDB |
|---|---|
Set a watchpoint on a variable when it is written to. | |
|
|
Set a watchpoint on a memory location when it is written to. | |
|
Note: The size of the region to watch for defaults to the pointer size if no |
Set a condition on a watchpoint. | |
— |
|
List all watchpoints. | |
|
|
Delete a watchpoint. | |
|
|
Examining Variables
GDB | LLDB |
|---|---|
Show the arguments and local variables for the current frame. | |
and
|
|
Show the local variables for the current frame. | |
|
|
Show the contents of the local variable | |
|
|
Show the contents of the local variable | |
|
|
Show the contents of the global variable | |
|
|
Show the global/static variables defined in the current source file. | |
— |
|
Display the variables | |
|
|
Display the variables | |
— |
|
Display the variable | |
— |
|
Mac List Symbols In Static Library In India
Evaluating Expressions
GDB | LLDB |
|---|---|
Evaluate a generalized expression in the current frame. | |
Or if you don’t want to see void returns:
|
Or use the
|
Create and assign a value to a convenience variable. | |
Or use the
Or use the
To specify the type of the variable:
| LLDB evaluates a variable declaration expression as you would write it in C:
|
Print the Objective-C | |
|
Or use the
|
Print the dynamic type of the result of an expression. | |
Note: Only for C++ objects. |
Or set dynamic type printing as default:
|
Call a function to stop at a breakpoint in the function. | |
|
|
Mac Keyboard Symbols List
Examining Thread State
Mac List Symbols In Static Library In Java
GDB | LLDB |
|---|---|
Show the stack backtrace for the current thread. | |
|
|
Show the stack backtraces for all threads. | |
|
|
Backtrace the first five frames of the current thread. | |
|
|
Select a different stack frame by index for the current thread. | |
|
|
List information about the currently selected frame in the current thread. | |
— |
|
Select the stack frame that called the current stack frame. | |
|
|
Select the stack frame that is called by the current stack frame. | |
|
|
Select a different stack frame using a relative offset. | |
|
|
Show the general-purpose registers for the current thread. | |
|
|
Write a new decimal value | |
|
|
Skip 8 bytes ahead of the current program counter (instruction pointer). | |
|
The LLDB command uses backticks to evaluate an expression and insert the scalar result. |
Show the general-purpose registers for the current thread formatted as signed decimal. | |
— |
LLDB now supports the GDB shorthand format syntax, but no space is permitted after the command:
Note: LLDB tries to use the same format characters as |
Show all registers in all register sets for the current thread. | |
|
|
Show the values for the registers named | |
|
|
Show the values for the register named | |
|
LLDB now supports the GDB shorthand format syntax, but no space is permitted after the command:
|
Read memory from address | |
|
LLDB now supports the GDB shorthand format syntax, but no space is permitted after the command:
|
Read memory starting at the expression | |
|
Note that any command can inline a scalar expression result (as long as the target is stopped) using backticks around any expression:
|
Read 512 bytes of memory from address | |
|
|
Save binary memory data to a file starting at | |
|
|
Disassemble the current function for the current frame. | |
|
|
Disassemble any functions named | |
|
|
Disassemble an address range. | |
|
|
Disassemble 20 instructions from a given address. | |
|
|
Show mixed source and disassembly for the current function for the current frame. | |
— |
|
Disassemble the current function for the current frame and show the opcode bytes. | |
— |
|
Disassemble the current source line for the current frame. | |
— |
|
Executable and Shared Library Query Commands
GDB | LLDB |
|---|---|
List the main executable and all dependent shared libraries. | |
|
|
Look up information for a raw address in the executable or any shared libraries. | |
|
|
Look up functions matching a regular expression in a binary. | |
| This one finds debug symbols:
This one finds non-debug symbols:
Provide a list of binaries as arguments to limit the search. |
Look up information for an address in | |
— |
|
Look up information for a type | |
|
|
Dump all sections from the main executable and any shared libraries. | |
|
|
Dump all sections in the | |
— |
|
Dump all symbols from the main executable and any shared libraries. | |
— |
|
Dump all symbols in | |
— |
|
Miscellaneous
Symbols On A Mac
GDB | LLDB |
|---|---|
Echo text to the screen. | |
|
|
Remap source file pathnames for the debug session. | |
|
Note: If your source files are no longer located in the same location as when the program was built—maybe the program was built on a different computer—you need to tell the debugger how to find the sources at the local file path instead of the build system file path. |
Supply a catchall directory to search for source files in. | |
| (No equivalent command yet.) |
Mac List Symbols In Static Library In Windows 10
Copyright © 2013 Apple Inc. All Rights Reserved. Terms of Use Privacy Policy Updated: 2013-09-18