From mboxrd@z Thu Jan  1 00:00:00 1970
From: ron@ronnatalie.com (Ron Natalie)
Date: Wed, 4 Jan 2017 11:58:41 -0500
Subject: [TUHS] Unix stories
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There's a trademark between allowing the compiler to reorder things and having a defined order of operations.
Steps like that are well-defined in Java for instance.   C lets the compiler do what it sees fit.

Note that it's not necessarily any better in assembler.    There are RISC architectures where load-followed-by-store and vice versa may not always be valid if done in quick succession.    Requiring the compiler to insert sequence points typically wastes a lot of cycles.    Assembler programmers tend to think about what they are doing, the C compiler tries to do some of this on its own and its not clairvoyant.