Yu GE's c ++ Study Notes (1) Compilation Method

To learn C ++, you must first select the learning environment. Starting the Linux/g ++/C ++ journey with the help of an expert ~

In Linux, start with G ++. Write pseudo in the editorCodeLet him change from a file to the output on the screen display requires a compilation process, which is handed over to the G ++ compiler. This process is divided into four phases:

• 1. Preprocessing;
• 2. Compile;
• 3. Assembly;
• 4. links;

Let's take a look at helloworld, 1:

Figure 1

G ++ Compilation:

-C *. cpp: Compile the file into *. O obj.

-O *. O: Compile the OBJ file as an output file.

See Figure 2:

Figure 2

Hello world is output successfully.

Further steps:

As shown in figure 1, the include and pre-defined variables are often put in the header file in the development environment, so that we can modify the code, 3, 4:

Figure 3: header file

Macro definition:

# Ifndef: prevents multiple inclusion of C files.

# Define win32_lean_and_mean: the MFC module is not loaded in Win32.

Figure 4: CPP File

G ++ compilation, 5:

Figure 5

Compilation error. How is it going? No file is displayed, indicating that the header file is not found. There is a difference between the Linux and Windows environments and the relative path is not prepared in CPP, in this way, G ++ uses-I to specify the position of the header file during compilation. 6:

Figure 6

Successful! This article describes how to debug helloworld:

• C ++ProgramStructure
• C ++ compilation process
• Usage of G ++ compilation commands

PS: Yu Ge is a C ++ beginner ~ Please give more suggestions to experts ~