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Well, the problem is solved and the solution may be of interest |
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to some Gentoo users. |
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|
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At first I thought that I was in for some heavy debugging, but the |
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fault was a simple matter (simple at least superficially). |
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|
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I have been using the latest gcc-4.5.1 for some time now and |
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I try to compile my system with all the newest optimizations, namely |
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the "-flto," "-floop-interchange," "-floop-strip-mine," and |
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"-floop-block" compiler flags which enables Graphite and LTO. |
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Usually I have no problems during an emerge but when I do the |
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temporary removal of the "-flto" option allows the emerge to finish. |
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So far there have been no issues with these flags. |
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|
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Now, whenever a problem with software is encountered the first question |
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to ask is what has been changed on the system. In my case it most |
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likely was the use of these compiler flags. So, on a lark, I decided |
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to re-emerge ghostscript with a basic set of CFLAGS = -O2 -march=native. |
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It worked. The problem I was having with all black images has |
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disappeared and ghostscript functions normally. |
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|
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However, I really cannot consider this to be normal behavior. Compiler |
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optimization should not degrade the function of a program. Something |
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subtle must be at fault with the gcc compiler. But being quite uninformed |
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about compiler design I cannot say much more. |
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|
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Anyway, thanks again for all those who did the test. This confirmed |
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that the problem was not ghostscript per se but rather a strange effect |
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on the ghostscript code caused by the compiler optimization. |
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|
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I can now see why the Gentoo deveolpers are being so cautious by considering |
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these latest GCC options as being experimental. |
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|
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Frank Peters |