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jeremybenn |
// { dg-do assemble }
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// { dg-options "" }
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// g++ 1.37.1 bug 900227_01
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// g++ allows pointer type values to be converted to integral types which are
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// not actually large enough to hold the converted values.
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// Section 3.3.4 of the ANSI C standard says:
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// A pointer may be converted to an integral type. The size of the
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// integer required and the results are implementation defined. If
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// the space provided is not long enough, the behavior is undefined.
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// I believe that the only proper thing to do in such cases is to generate
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// errors. After all, if the converted value gets truncated, it is not
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// likely to be useful after that.
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// Furthermore, as the following example demonstrates, allowing pointers
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// to be converted to integral types which are not of sufficient size to
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// completely hold the converted values may cause additional troubles.
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// I tried the following code on 5 different machines and it failed on
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// all five (unless I also use the GNU assembler and the GNU linker). Three
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// of the five (Sun3, Sun4, and Symmetry) got link-time errors about byte
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// offset overflows. The other two (368/SystemV and AViiON) got assembly
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// time errors about relocatable names used in "constant" expressions.
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// keywords: casts, pointer types, integral types
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// Update 2/10/95: The compiler will now compute these expressions at
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// runtime. I think this is in the spirit of the GNU compilers (jason).
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int main ();
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short s = (short) &main; // { dg-warning "" "" { xfail h8*-*-* xstormy16-*-* } } small integer
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char c = (char) &main; // { dg-warning "" } small integer
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int main () { return 0; }
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