Clang Compiler Models

There are two Clang compiler models: clang and clangpp.

• Overview
• Availability
• Model-Specific ABI Key Format
• LLVM Clang vs Apple Clang
• Command Arguments
• Predefined Macros, Include Paths, Front End Options

Overview

The clang compiler model is based on the gcc model. The clangpp compiler model is based on the clang model, and thus transitively on the gcc model.

The only difference between the clang and clangpp models is is that compilations modeled with the clangpp model are always modeled in C++ mode unless the language is explicitly specified using the -x flag.

The following file extensions are supported.

Availability

For full details of all native compilers recognized by CodeSonar by default, see section Compilers Recognized by CodeSonar.

Model-Specific ABI Key Format

The clang and clangpp compiler models are based on the gcc model, so you can associate an ABI key in the gcc-model-specific format with any compilation handled by the clang or clangpp model. The key structure and interpretation are described in GNU Compiler Models: Model-Specific ABI Key Format.

LLVM Clang vs Apple Clang

The clang and clangpp compiler models can be used for both LLVM Clang and Apple Clang compilations. However, there are some differences between the two, so the models attempt to invoke the native compiler to determine which of the two it corresponds to.

If this determination cannot be performed, the model defaults to assuming that you are using LLVM Clang.

If the model determines that you are using Apple Clang, it performs two additional actions.

• It specifies front end option --cs_apple_clang.
• It computes the LLVM Clang version equivalent to the version self-reported by the native compiler executable using the following conversion scheme.
  This computed value is used to determine version-based behavior for macro settings and front end options).

  Native Compiler Version ver	Equivalent LLVM Version Computed by Model
  1.0 ≤ ver < 4.1	3.1
  4.1 ≤ ver < 5.0	3.2
  ver = 5.0	3.3
  5.0 < ver < 6.0	3.4
  ver = 6.0	3.5
  6.0 < ver < 7.0	3.6
  7.0 ≤ ver < 7.3	3.7
  7.3 < ver < 8.0	3.8
  8.0 ≤ ver < 9.0	3.9
  9.0 ≤ ver < 10.0	4.0
  10.0 ≤ ver < 11.0	6.0
  11.0 ≤ ver < 12.0	8.0
  otherwise	8.0

The default C++ standard also depends on whether or not the modeled native compiler is determined to be Apple Clang.

Command Arguments

Command argument handling for the clang and clangpp compiler models is the same as that for the gcc model (described in GNU Compiler Models: Command Arguments), with the following additions.

Compilation Mode

The modeled compilation mode is determined as follows.

C and C++ Standards

The applicable C or C++ standard for the modeled compilation is determined as follows.

• If -std arg is specified, the applicable C or C++ standard is determined by the value of arg.

  arg	Standard Set
  	C	C++
  c89	C89	-
  c90 iso9899:1990 iso9899:199409 gnu89 gnu90	C90	-
  c99 c9x gnu99 gnu9x iso9899:1999 iso9899:199x	C99	-
  c11 c1x gnu11 gnu1x c17 c18 gnu17 gnu18 iso9899:2017 iso9899:2018 c2x	C11	-
  c++98 gnu++98	-	C++98
  c++03 gnu++03	-	C++03
  c++0x gnu++0x	-	C++0x
  c++11 gnu++11	-	C++11
  c++14 c++1y gnu++14 gnu++1y	-	C++14
  c++17 c++1z gnu++17 gnu++1z	-	C++17
  c++2a gnu++2a	-	C++20
  other arg	-	-

• Otherwise, the applicable standard is based on the Clang version determined by the model and, for C++, on whether or not the native compiler is Apple Clang.

  C standard	C11 if Clang version is 3.6 or later,	C99 otherwise.	If you are using Apple Clang (as opposed to LLVM Clang), note that this is the computed Clang version resulting from the translation described above.
  C++ standard	C++14 if Clang version is 6.0 or later, or if the native compiler is Apple Clang;	C++98 otherwise.

No CodeSonar Build

If any of the following are specified, CodeSonar will ignore the compilation and will not generate any corresponding internal representation. If a CodeSonar project is based only on ignored compilations, it will have no contents and so will not be finalized.

• Any command argument listed in GNU Compiler Models: No CodeSonar Build.
• -ObjC, -ObjC++

Predefined Macros, Include Paths, Front End Options

Predefined macros for the clang and clangpp compiler models are the same as those for the gcc model (described in GNU Compiler Models: Predefined Macros and Include Paths), with the following exceptions.

If you are using Apple Clang (as opposed to LLVM Clang), note that the "Clang version" upon which some conditional definitions depend is the version resulting from the translation described above.