olena

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Software platform for efficient and generic image processing. It is composed of a Generic and efficient C++ image processing library, a framework for Document Image Analysis and Python bindings.

[ryandesign (Ryan Carsten Schmidt)]

The maintainers line must be a valid email address (preferably in our obfuscated form), or "nomaintainer".

This port does not work on PowerPC Macs?

Can you explain why adding CXXFLAGS=-fno-strict-aliasing on Lion was necessary? What error occurred otherwise? What compiler was being used? Does the problem not affect Snow Leopard when using that same compiler?

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Maintainers field updated.

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We haven't tried on PowerPC yet that is why we have chosen X86 only. We will manage to get a Power PC in a few weeks but this is not our priority.

CXXFLAGS=-fno-strict-aliasing is useful on Lion only. With some variants of gcc 4.2 while compiling with '-O3', binaries produced are wrong and crash. Snow Leopard and Lion both use Apple's gcc 4.2 however this is not the same exact version.

We have encountered issues on Lion with : i686-apple-darwin11-llvm-gcc-4.2 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.15.00). Using this flag, make it work. This is because we do some magic with pointers in some parts of our code and this particular version of gcc gets confused with it.

With other standard gcc compilers provided through mac ports, no issue have been encountered. This project is tested under Debian Linux using gcc 4.1, 4.2, 4.4, 4.6 and on Mac OS Lion/Snow Leopard with llvm-gcc-4.2.

[jmroot (Joshua Root)]

If you're violating C/C++ aliasing rules, you need to pass -fno-strict-aliasing all the time. Otherwise you're hitting undefined behaviour, and any unwanted results are not a bug in the compiler, they're a bug in your code. (Turning off strict aliasing does come with a performance penalty, so you're better off to just obey the aliasing rules.)

[jmroot (Joshua Root)]

r94602