2.5.3-pre1 compile error
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Quoted 7 lines · dmeyer
In article <[email protected]> you write:
Quoted 5 lines
I'm sure I read somewhere that gcc is clever enough to know when it hits a #include, it checks for a symbol equal to a mangled version of the filename before including it. (Ie, doing this transparently).
Then again, I may have imagined it all.
No, you read that gcc notices when the entirety of a source file is wrapped in an #ifdef guard and won't re-read that file when it's included again if the symbol is defined.
Quoted 3 lines
In answer to Linus' question...yes, in a large system redundent include guards can make a real difference, particularly for headers which get included by other headers regularly.
Yes, but you don't need to put them around the #include. Just make sure there is nothing but comments outside the multiple inclusion guards in the header files and any competent compiler will do the right thing.
Signature · 1 line
Russ Allbery ([email protected]) <http://www.eyrie.org/~eagle/>