debug (Linux* and OS X*)

Enables or disables generation of debugging information.

Syntax

Linux and OS X:

-debug [keyword]

Windows:

None

Arguments

keyword

Is the type of debugging information to be generated. Possible values are:

none	Disables generation of debugging information.
full or all	Generates complete debugging information.
minimal	Generates line number information for debugging.
[no]emit_column	Determines whether the compiler generates column number information for debugging.
[no]expr-source-pos	Determines whether the compiler generates source position information at the expression level of granularity.
[no]inline-debug-info	Determines whether the compiler generates enhanced debug information for inlined code.
[no]macros	Determines whether the compiler emits debugging information for C/C++ macros.
[no]pubnames	Determines whether the compiler generates a DWARF debug_pubnames section.
[no]semantic-stepping	Determines whether the compiler generates enhanced debug information useful for breakpoints and stepping.
[no]variable-locations	Determines whether the compiler generates enhanced debug information useful in finding scalar local variables.
extended	Sets keyword values semantic-stepping and variable-locations.
[no]parallel (Linux only)	Determines whether the compiler generates parallel debug code instrumentations useful for thread data sharing and reentrant call detection.

For information on the non-default settings for these keywords, see the Description section.

Default

varies

Normally, the default is -debug none and no debugging information is generated. However, on Linux* OS, the -debug inline-debug-info option will be enabled by default if you compile with optimizations (option -O2 or higher) and debugging is enabled (option -g).

Description

This option enables or disables generation of debugging information.

Note that if you turn debugging on, optimization is turned off.

Keywords semantic-stepping, inline-debug-info, variable-locations, and extended can be used in combination with each other. If conflicting keywords are used in combination, the last one specified on the command line has precedence.

Option	Description
-debug none	Disables generation of debugging information.
-debug full or -debug all	Generates complete debugging information. It is the same as specifying -debug with no keyword.
-debug minimal	Generates line number information for debugging.
-debug emit_column	Generates column number information for debugging.
-debug expr-source-pos	Generates source position information at the statement level of granularity.
-debug inline-debug-info	Generates enhanced debug information for inlined code. On inlined functions, symbols are (by default) associated with the caller. This option causes symbols for inlined functions to be associated with the source of the called function.
-debug macros	The compiler emits debugging information for C/C++ macros. This provides a means to describe the macros for a given compilation unit.
-debug pubnames	The compiler generates a DWARF debug_pubnames section. This provides a means to list the names of global objects and functions in a compilation unit.
-debug semantic-stepping	Generates enhanced debug information useful for breakpoints and stepping. It tells the debugger to stop only at machine instructions that achieve the final effect of a source statement. For example, in the case of an assignment statement, this might be a store instruction that assigns a value to a program variable; for a function call, it might be the machine instruction that executes the call. Other instructions generated for those source statements are not displayed during stepping. This option has no impact unless optimizations have also been enabled.
-debug variable-locations	Generates enhanced debug information useful in finding scalar local variables. It uses a feature of the Dwarf object module known as "location lists". This feature allows the run-time locations of local scalar variables to be specified more accurately; that is, whether, at a given position in the code, a variable value is found in memory or a machine register.
-debug extended	Sets keyword values semantic-stepping and variable-locations. It also tells the compiler to include column numbers in the line information.
-debug parallel	Generates parallel debug code instrumentations needed for the thread data sharing and reentrant call detection. For shared data and reentrancy detection, option -qopenmp must be set.

On Linux* systems, debuggers read debug information from executable images. As a result, information is written to object files and then added to the executable by the linker.

On OS X* systems, debuggers read debug information from object files. As a result, the executables don't contain any debug information. Therefore, if you want to be able to debug on these systems, you must retain the object files.

IDE Equivalent

Visual Studio: None

Eclipse: Debug > Enable Parallel Debug Checks (-debug parallel)

Debug > Enable Expanded Line Number Information (-debug expr-source-pos)

Xcode: None

Alternate Options

For -debug full, -debug all, or -debug

Linux and OS X: -g

Windows: /debug:full, /debug:all, or /debug

For -debug variable-locations

Linux and OS X: -fvar-tracking

Windows: None

For -debug semantic-stepping

Linux and OS X: -fvar-tracking-assignments