Week 4: Compilation and Singly Linked List

Tae-Hyuk (Ted) AhnDepartment of Computer Science

Program of Bioinformatics and Computational BiologySaint Louis University

CSCI 2100 Data Structures Fall 2019

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Student OutcomesAfter this lecture, students are expected to understand

● Compile and build with multiple files including header file.

● Develop a singly-linked list

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A Brief History and Introduction to GCCThe original GNU C Compiler (GCC) is developed by Richard Stallman, the founder of the GNU Project. Richard Stallman founded the GNU project in 1984 to create a complete Unix-like operating system as free software, to promote freedom and cooperation among computer users and programmers.

● GCC, formerly for "GNU C Compiler", has grown over times to support many languages such as C (gcc), C++ (g++), Objective-C, Objective-C++, Java (gcj), Fortran (gfortran), Ada (gnat), Go (gccgo), OpenMP, Cilk Plus, and OpenAcc. It is now referred to as "GNU Compiler Collection". The mother site for GCC is http://gcc.gnu.org/.

● GCC is a key component of so-called "GNU Toolchain", for developing applications and writing operating systems. The GNU Toolchain includes:§ GNU Compiler Collection (GCC): a compiler suite that supports many languages, such as C/C++ and Objective-C/C++.§ GNU Make: an automation tool for compiling and building applications.§ GNU Binutils: a suite of binary utility tools, including linker and assembler.§ GNU Debugger (GDB).§ GNU Autotools: A build system including Autoconf, Autoheader, Automake and Libtool.§ GNU Bison: a parser generator (similar to lex and yacc).

● GCC is portable and run in many operating platforms. GCC (and GNU Toolchain) is currently available on all Unixes. They are also ported to Windows (by Cygwin, MinGW and MinGW-W64). GCC is also a cross-compiler, for producing executables on different platform.

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GCC Versions

The various GCC versions are:

● GCC version 1 (1987): Initial version that support C.

● GCC version 2 (1992): supports C++.

● GCC version 3 (2001): incorporating ECGS (Experimental GNU Compiler System), with improve optimization.

● GCC version 4 (2005):

● GCC version 5 (2015):

● GCC Version 6 (2016):

● GCC Version 7 (2017):

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C++ Standard Support

There are various C++ standards:

● C++98

● C++11 (aka C++0x)

● C++14 (aka C++1y)

● C++17 (aka C++1z)

● C++2a (next planned standard in 2020)

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C++ versions

● What version of C++ am I using now?

● What version of g++ am I using now?

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My g++ version check

https://gcc.gnu.org/projects/cxx-status.htmlhttps://gcc.gnu.org/onlinedocs/gcc/Standards.html

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How to explicitly compile using C++11,14,17?$ g++ -std=c++11 source.cpp –o output$ g++ -std=c++14 source.cpp –o output

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The compilation of a C++

● Preprocessing: the preprocessor takes a C++ source code file and deals with the #includes, #defines and other preprocessor directives. The output of this step is a "pure" C++ file without pre-processor directives.

● Compilation: the compiler takes the pre-processor's output and produces an object file from it.

● Linking: the linker takes the object files produced by the compiler and produces either a library or an executable file.

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Compiling and Linking

$ g++ -o main.exe main.cpp

$ g++ -c main.cpp$ g++ -o main.exe main.o

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Separating class code into a header and cpp file

Ask

$ g++ -o main.exe add.cpp main.cpp

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GCD project with three files

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rectangle.h

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rectangle.cpp

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rectangle_test.cpp

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makefile● Finally, we note that for larger problems, there are other tools to assist developers in managing their

projects. ● For example, many Integrated Development Environments (IDEs) will keep track of which pieces of

source code have been modified, and which need to be re-compiled when building a new executable. ● One of the classic tools for developers in managing the (re)building of a project is a program known

as make. This program relies upon a configuration file for the project, conventionally named makefile.

● The makefile designates what components comprise the project, and upon which pieces of source code each component depends. The make command causes a re-build of the entire project, but relying on the file-system timestamps to determine which pieces of source code have been edited since the previous build.

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Object demo and makefile examplehopper:/public/ahnt/courses/csci2100/demos/objectdemo