Alessandro Bonazzi
e075990ed3
Files correlati : Commento : Aggiunto il preprocessore c++ mcpp per sostituire il compilatore nella compilazione delle maschere.
25 lines
1.1 KiB
C
25 lines
1.1 KiB
C
/* u_1_22.c: Undefined behaviors on generating invalid pp-token by # and
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## operators. */
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/* { dg-do preprocess } */
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/* u.1.22: Result of ## operator is not a valid pp-token. */
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#define NUM( dig, exp) dig ## E+ ## exp
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/*
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* "E+" is a sequence of two pp-tokens "E" and "+", not a single pp-token.
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* The first ## concatenates the last pp-token of first argument with "E",
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* and the second ## concatenates "+" with the first pp-token of the second
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* argument.
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* While "12E" (one of the sequence generated by the token concatenation)
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* is a valid pp-token, "+34" (the another sequence) is not a valid pp-token
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* and causes an undefined behavior.
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*/
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NUM( 12, 34); /* { dg-error "(n|N)ot (give |)a valid preprocessing token" } */
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/* u.1.23: Result of # operator is not a valid string literal. */
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/* "\\"\""; This sequence is parsed to three tokens "\\" \ "", and will be
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diagnosed by compiler-proper unless diagnosed by preprocessor. */
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#define str( a) #a
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str( \""); /* { dg-error "(n|N)ot (give |)a valid string literal" } */
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