int a = a (Was: Bart's Language)

In article <vrc75b$2r4lt$1@dont-email.me>,
David Brown  <david.brown@hesbynett.no> wrote:
...

gcc won't warn until you say '-Wextra', and then only for:
>
   int a = a + 1;

>
People would not normally write "int a = a;".  It is used as a common
idiom meaning "I know it is not clear to the compiler that the variable
is always initialised before use, but /I/ know it is - so disable the
use-without-initialisation warnings for this variable".  So it makes
perfect sense for the compiler not to warn about it!

Wouldn't it just be easier and clearer to write: int a = 0;
and be done with it?

"int a = a + 1;", on the other hand, clearly attempts to read the value
of "a" before it is initialised, and a warning is issued if
"-Wuninitialized" is enabled.  This warning is part of "-Wall".

How is: int a = a + 1;
conceptually different from: int a = a;

Both are expressions involving 'a'.
Isn't 'a' being used un-initialised in both cases?

(You have to know the value of 'a' in order to evaluate the expression: a)

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"If our country is going broke, let it be from feeding the poor and caring for
the elderly. And not from pampering the rich and fighting wars for them."

    --Living Blue in a Red State--