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56 lines
1.9 KiB
Plaintext
56 lines
1.9 KiB
Plaintext
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This is a partial list of how `gcc -traditional' disagrees with
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traditional C compilers (perhaps only some of them). Most of these
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differences are not bugs.
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---------------------------------------------------------------------------
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K&R-1 (2.4.3) says:
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"If the character following a backslash is not one of those
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specified {in the table above}, the backslash is ignored."
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Up until recently, `gcc -traditional' complained about \x \a and \v
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appearing in a character or string literal. I believe however that
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this non-feature has been eliminated (recently).
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---------------------------------------------------------------------------
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When in -traditional mode, gcc allows the following erroneous pair of
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declarations to appear together in a given scope:
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typedef int foo;
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typedef foo foo;
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---------------------------------------------------------------------------
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K&R-1 (8.5) says:
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"No field may be wider than a word."
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Gcc however allows:
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struct S { int i:33; };
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---------------------------------------------------------------------------
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In K&R-1 there is no restriction against comments crossing include file
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boundaries. Gcc however doesn't allow this, even when in -traditional mode.
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---------------------------------------------------------------------------
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Regarding the length of identifiers, K&R-1 (2.2) says:
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"No more than the first eight characters are significant,
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although more may be used."
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Gcc treats all characters of identifiers as significant, even when in
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-traditional mode.
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---------------------------------------------------------------------------
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K&R-1 (2.2) says:
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"An identifier is a sequence of letters and digits; the first
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character must be a letter. The underscore _ counts as a letter."
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Gcc also allows dollar signs in identifiers. (This may also be an issue
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for the -pedantic option.)
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---------------------------------------------------------------------------
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