c89-gcc

c89-gcc [options] [files]...

[files]...
    One or more input C source files (e.g., filename.c) or object files to be compiled.

-o
    Specify the name of the output executable or object file. This is a common gcc option.

-c
    Compile or assemble the source files, but do not link them. This produces object files (e.g., .o files).

-Wall
    Enable all commonly used warnings, useful for catching potential issues in the code.

-I

c89-gcc is typically a wrapper script or a symbolic link to the GNU C Compiler (gcc) specifically configured to compile C source code strictly according to the C89 (ISO/IEC 9899:1990) standard, also known as ANSI C.

When executed, c89-gcc implicitly passes the -std=c89 (or sometimes -ansi) option to gcc. This ensures that the compiler adheres to the original C standard, disallowing features introduced in newer C standards (like C99, C11, C17) or GNU extensions by default, and issuing warnings or errors for non-compliant code.

It is particularly useful for maintaining legacy code, ensuring maximum portability across diverse or older systems, or developing applications that must strictly conform to the C89 specification for specific project requirements.

c89-gcc is not a standard command universally present on all Linux distributions. Its existence and behavior depend on how gcc is configured or if a custom wrapper script has been created by the system administrator or a toolchain. It might be a simple symbolic link or a more complex shell script. Its primary limitation is the forced adherence to the C89 standard, which means modern C features are not available for use.

While gcc's default C standard has evolved over time (e.g., to C99, C11, or GNU C), c89-gcc explicitly forces compilation under the older C89 standard. This can lead to compilation errors or warnings if the source code uses features from newer C standards or GNU extensions not permitted by C89.

Using c89-gcc is beneficial when developing highly portable C applications that need to compile without issues on very old systems or compilers, or when maintaining and extending existing legacy codebases that predate newer C standards and rely solely on C89 constructs.

The C89 standard, formally ISO/IEC 9899:1990 (also known as ANSI C), was a landmark in C programming, providing the first widely accepted international standard for the language. The GNU C Compiler (gcc) has supported this standard through options like -ansi or -std=c89 since its early development. The creation of a dedicated c89-gcc command likely arose in environments or specific toolchains where strict C89 compliance was a frequent requirement, simplifying the compilation process by encapsulating the necessary gcc options into a single, convenient command.

gcc(1), cc(1), make(1), ld(1)