part of shnell – a source to source compiler enhancement tool

© Jens Gustedt, 2019

Implement C2x’ new attribute syntax

This relies on legacy methods provided by common compilers such as gcc’s __attribute__.

You should provide your idea of the legacy compiler to use through the environment variable ATTRIBUTES. This should provide the implementation specific prefix and is used to guess the implementation-specific syntax that implement attributes.

We currently support the following values:

• gnu is the GNU compiler gcc. It supports all current standard attributes as well as large number of implementation specific ones. The syntax is rewritten to something like __attribute__((tokens)).

• clang is treated a superset to gnu.

• std is meant for compilers that don’t need rewriting, because they fully implement the attribute feature. Attribute tokens are rewritten to the form that has leading and trailing double underscores. Syntactically correct implementation-specific attributes are otherwise passed through. Other unknown attributes are removed.

• portability is the same as std but all implementation-specific attributes are removed.

• gsl is for the Microsoft compilers. The support the standard attributes but not much more. The resulting syntax is __declspec.

Coding and configuration

The following code is needed to enable the sh-module framework.

SRC="$_" . "${0%%/${0##*/}}/import.sh"

Imports

The following sh-modules are imported:

• join
• tokenize
• ballanced
• list
• tmpd

Details