[8833] | 1 | This is a partial list of how `gcc -traditional' disagrees with |
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| 2 | traditional C compilers (perhaps only some of them). Most of these |
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| 3 | differences are not bugs. |
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| 4 | |
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| 5 | --------------------------------------------------------------------------- |
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| 6 | K&R-1 (2.4.3) says: |
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| 7 | |
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| 8 | "If the character following a backslash is not one of those |
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| 9 | specified {in the table above}, the backslash is ignored." |
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| 10 | |
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| 11 | Up until recently, `gcc -traditional' complained about \x \a and \v |
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| 12 | appearing in a character or string literal. I believe however that |
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| 13 | this non-feature has been eliminated (recently). |
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| 14 | |
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| 15 | --------------------------------------------------------------------------- |
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| 16 | When in -traditional mode, gcc allows the following erroneous pair of |
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| 17 | declarations to appear together in a given scope: |
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| 18 | |
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| 19 | typedef int foo; |
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| 20 | typedef foo foo; |
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| 21 | |
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| 22 | --------------------------------------------------------------------------- |
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| 23 | K&R-1 (8.5) says: |
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| 24 | |
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| 25 | "No field may be wider than a word." |
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| 26 | |
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| 27 | Gcc however allows: |
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| 28 | |
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| 29 | struct S { int i:33; }; |
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| 30 | |
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| 31 | --------------------------------------------------------------------------- |
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| 32 | In K&R-1 there is no restriction against comments crossing include file |
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| 33 | boundaries. Gcc however doesn't allow this, even when in -traditional mode. |
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| 34 | |
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| 35 | --------------------------------------------------------------------------- |
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| 36 | Regarding the length of identifiers, K&R-1 (2.2) says: |
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| 37 | |
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| 38 | "No more than the first eight characters are significant, |
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| 39 | although more may be used." |
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| 40 | |
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| 41 | Gcc treats all characters of identifiers as significant, even when in |
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| 42 | -traditional mode. |
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| 43 | |
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| 44 | --------------------------------------------------------------------------- |
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| 45 | K&R-1 (2.2) says: |
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| 46 | |
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| 47 | "An identifier is a sequence of letters and digits; the first |
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| 48 | character must be a letter. The underscore _ counts as a letter." |
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| 49 | |
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| 50 | Gcc also allows dollar signs in identifiers. (This may also be an issue |
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| 51 | for the -pedantic option.) |
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| 52 | |
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| 53 | --------------------------------------------------------------------------- |
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| 54 | |
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| 55 | |
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