Compiler Built-ins Detection Support Overview

JSON Compilation Database Parser support can detect compiler-built-in include paths and preprocessor macros.

Invariant Built-ins Detection Support

The following table shows the compilers and their supported features detected.

Compiler	Vendor	Macros	System include paths	Local include paths	MACOS Framework include paths
gcc	GNU Project	tested	tested	tested	NYI [1]
clang	LLVM Project	tested	tested	tested	NYI [2]
cl	Microsoft	N/A	N/A	N/A	N/A

Support status above is either:

tested: detection is known to work
implemented (impl): support is implemented, but not (yet) known to work
not yet implemented (NYI): support is not implemented
not available (N/A): the compiler does not support detection (regarding the online docs only)

Compilers supported through separate plug-ins

Enhanced Built-ins Detection Support

Some compilers, mainly those of the GNU Compiler Collection and derivatives, report different built-ins depending on the arguments passed to the compiler. These arguments specify a non-default language level or specify non-standard default system include directories. The table below shows an overview of the supported compilers and the recognized command-line options.

Compiler	Vendor	Language Standard options	Non-Standard System include paths options	Other options
gcc	GNU Project	`-std=`, `-ansi`: tested	`--sysroot=`, `-isysroot=`, `--no-sysroot-prefix`: tested	`-fPIC`, `-fpic`, `-fPIE`, `-fpie` `-fstack-protector*`, `-march=`, `-march=`, `-mcpu=`, `-mtune=`, `-pthread`
clang	LLVM Project	`-std=`, `-ansi`: tested	`--sysroot=`, `-isysroot=`, `--no-sysroot-prefix`: tested

Remarks:

[1] Help wanted! To implement this, the output of gcc -E -P -dM -Wp,-v emty.c running on OSX is needed.
[2] Help wanted! To implement this, the output of clang -E -P -dM -Wp,-v emty.c running on OSX is needed.