This macro checks if the compiler supports one of GCC’s variable attributes; many other compilers also provide variable attributes with the same syntax. Compiler warnings are used to detect supported attributes as unsupported ones are ignored by default so quieting warnings when using this macro will yield false positives.
The ATTRIBUTE parameter holds the name of the attribute to be checked.
If ATTRIBUTE is supported define HAVE_VAR_ATTRIBUTE_<ATTRIBUTE>.
The macro caches its result in the ax_cv_have_var_attribute_<attribute> variable.
The macro currently supports the following variable attributes:
aligned cleanup common nocommon deprecated mode packed tls_model unused used vector_size weak dllimport dllexport init_priority
Unsuppored variable attributes will be tested against a global integer variable and without any arguments given to the attribute itself; the result of this check might be wrong or meaningless so use with care.
Download the latest version of ax_gcc_var_attribute.m4 or browse the macro’s revision history.
Copyright © 2013 Gabriele Svelto email@example.com
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