Andriy Gapon 970165f190 MFV r323111: 8569 problem with inline functions in abd.h ... illumos/illumos-gate@37e84ab74e 37e84ab74e https://www.illumos.org/issues/8569 C [C99] has peculiar rules for inline functions that are different from the C++ rules. Unlike C++ where inline is "fire and forget", in C a programmer must pay attention to the function's storage class / visibility. The main problem is with the case where a compiler decides to not inline a call to the function declared as inline. Some relevant links: - http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka15831.html - http://www.drdobbs.com/the-new-c-inline-functions/184401540 The summary is that either the inline functions should be declared 'static inline' or one of the compilation units (.c files) must provide a callable externally visible function definition. In the former case, the compiler would automatically create a local non-inlined function instance in every compilation unit where it's needed. In the latter case the single external definition is used to satisfy any non-inlined calls in all compilation units. As things stand right now, we can get an undefined reference error under certain combinations of compilers and compiler options. For example, this is what I get on FreeBSD when compiling with clang 4.0.0 and -O1: In function `abd_free': /usr/src/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/abd.c:385: undefined reference to `abd_is_linear' Reviewed by: Matt Ahrens <mahrens@delphix.com> Approved by: Robert Mustacchi <rm@joyent.com> Author: Andriy Gapon <avg@FreeBSD.org> MFC after: 1 week		2017-09-11 12:15:49 +00:00
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common	zfs: do not advertise edonr which is not yet supported	2017-08-29 22:24:22 +00:00
uts	MFV r323111: 8569 problem with inline functions in abd.h	2017-09-11 12:15:49 +00:00
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