GPRconfig Reference

GPRconfig probes the host for available compilers and generates a configuration project (.cgpr) that describes the selected toolchains to all GPR tools. It can be used interactively or in batch mode from a script.

GPRconfig is independent of any GPR project tree. It does not accept the common project and configuration switches described in Common Command-Line Options; its option set is documented entirely in this chapter.

Command Line

Syntax

gprconfig [switches]

Compiler selection

GPRconfig scans PATH (and any directories added by --config) for compiler executables, cross-references them against the knowledge base, and builds a list of available compilers. In interactive mode the user selects which compilers to include; in batch mode (--batch) the selection is driven entirely by --config options on the command line.

At most one compiler per language may be selected. The output configuration project contains one package Compiler section per selected language.

Switches

Target and output

--target=name: Select compilers for the given target. Use all to list compilers for every available target. Defaults to the native target. In batch mode, --target=all is silently ignored.
-o file: Write the generated configuration project to file. Defaults to default.cgpr when no target is specified, or <target>.cgpr when a target is given.
--show-targets: Print the list of targets for which at least one compiler is available in the knowledge base, then exit. The native target is marked (native target).
--mi-show-compilers: Print a machine-readable list of all available compilers and exit. Each compiler is described as a set of key=value pairs; compilers already selected for output are prefixed with *. Intended for IDE integration.
--show-known-compilers: Print the names of all compiler blocks defined in the knowledge base, then exit.

Compiler selection (batch mode)

--batch

Run in batch (non-interactive) mode. No prompts are displayed. The compilers to include must be specified entirely via --config options.

--config=selector

Pre-select a compiler. May be repeated, at most once per language.

The selector has two equivalent forms:

Positional: language[,version[,runtime[,path[,name]]]]

ada
ada,12.1
ada,,zfp
ada,,zfp,/opt/gnat/bin,gnat

Named: key:value[,key:value...]

language:ada
language:ada,version:12.1
language:ada,runtime:zfp
language:ada,runtime:zfp,path:/opt/gnat/bin,name:gnat

Available keys/fields:

language: Required. Language identifier (ada, c, c++, …).
version: Optional. Compiler version string (e.g. 12.1).
runtime: Optional. Runtime variant (e.g. sjlj, zfp, ravenscar).
path: Optional. Directory containing the compiler executable.
name: Optional. Compiler name as defined in the knowledge base (e.g. GCC, GNAT) or the base name of the compiler executable (e.g. gcc, arm-elf-gnatmake).

Omitted optional fields match any value. An empty string also matches any value, so ada,,zfp is equivalent to language:ada,runtime:zfp.

--fallback-targets

When no compiler is found for the requested target, also search for toolchains recorded as fallbacks, such as a compatible native target of a different architecture.

Knowledge base

--db dir: Parse dir as an additional knowledge base directory (may be repeated).
--db-: Do not load the standard knowledge base. Use together with --db to load a completely custom knowledge base.
--validate: Validate the knowledge base before use and report any schema errors, then proceed normally.

Diagnostics

-v: Verbose output. Repeat (-v -v) for even more detail, including internal knowledge base traces.
-q: Quiet: suppress all output except errors.

Interactive mode

When run without --batch, GPRconfig displays the list of compilers found for the selected target (one per line, with an index), prompts the user to select or deselect entries by typing their index number, and writes the configuration when the user types s. Selecting a compiler for a language automatically deselects any previously selected compiler for the same language.

After saving, GPRconfig prints the equivalent --batch command line so that the same selection can be reproduced in scripts.

Configuration file format

The generated file is a valid GPR configuration project (configuration qualifier, .cgpr extension). It defines:

package Compiler - compiler driver, default switches, dependency file format, and naming conventions for each selected language.
package Linker - linker driver and default flags.
package Binder - binder driver (for Ada).
package Archive_Builder - archiver command.
Top-level attributes - Target, Canonical_Target, Runtime_Library_Dir, Object_Generated, Library_Support, Shared_Library_Prefix, Shared_Library_Suffix, and related platform attributes.

The file is consumed by GPRbuild and the other project-based tools via --config or --autoconf. It is not a user project file and is not referenced by with clauses.

Exit Codes

0: Success; configuration file written (or information displayed).
1: No compiler found for the requested target or language, knowledge base error, or configuration generation failure.
7: Invalid command-line option.