---
name: "gccmakedep"
section: "1"
platform: "linux"
package: "imake"
version: "1.0.11-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/gccmakedep"
---

# gccmakedep(1)

create dependencies in makefiles using 'gcc -M'

## NAME

gccmakedep - create dependencies in makefiles using 'gcc -M'

## SYNOPSIS

**gccmakedep** \[ **-s***separator* \] \[ **-f***makefile* \] \[ **-a** \] \[ -- *options* -- \] *sourcefile* ...

## DESCRIPTION

The **gccmakedep** program calls 'gcc -M' to output *makefile* rules describing the dependencies of each *sourcefile*, so that [**make**(1)](/make/1.md) knows which object files must be recompiled when a dependency has changed.

By default, **gccmakedep** places its output in the file named *makefile* if it exists, otherwise *Makefile.* An alternate makefile may be specified with the **-f** option. It first searches the makefile for a line beginning with

    \# DO NOT DELETE

or one provided with the **-s** option, as a delimiter for the dependency output. If it finds it, it will delete everything following this up to the end of the makefile and put the output after this line. If it doesn't find it, the program will append the string to the makefile and place the output after that.

## EXAMPLE

Normally, **gccmakedep** will be used in a makefile target so that typing 'make depend' will bring the dependencies up to date for the makefile. For example,

```
    SRCS = file1.c file2.c ...
    CFLAGS = -O -DHACK -I../foobar -xyz
    depend:
            gccmakedep -- $(CFLAGS) -- $(SRCS)
```

## OPTIONS

The program will ignore any option that it does not understand, so you may use the same arguments that you would for [**gcc**(1)](/gcc/1.md), including **-D** and **-U** options to define and undefine symbols and **-I** to set the include path.

- **-a**

  Append the dependencies to the file instead of replacing existing dependencies.

- **-f***makefile*

  Filename. This allows you to specify an alternate makefile in which **gccmakedep** can place its output. Specifying “-” as the file name (that is, **-f-**) sends the output to standard output instead of modifying an existing file.

- **-s***string*

  Starting string delimiter. This option permits you to specify a different string for **gccmakedep** to look for in the makefile. The default is “# DO NOT DELETE”.

- **--** *options* **--**

  If **gccmakedep** encounters a double hyphen (--) in the argument list, then any unrecognized arguments following it will be silently ignored. A second double hyphen terminates this special treatment. In this way, **gccmakedep** can be made to safely ignore esoteric compiler arguments that might normally be found in a CFLAGS **make** macro (see the **EXAMPLE** section above). **-D**, **-I**, and **-U** options appearing between the pair of double hyphens are still processed normally.

## SEE ALSO

[**gcc**(1)](/gcc/1.md), [**make**(1)](/make/1.md), [**makedepend**(1)](/makedepend/1.md).

## AUTHOR

The version of the  **gccmakedep** included in this X.Org Foundation release was originally  written by the XFree86 Project based on code supplied by Hongjiu Lu.

Colin Watson wrote this manual page, originally for the Debian Project, based partly on the manual page for [**makedepend**(1)](/makedepend/1.md).