Strange Warnings

Strange Warnings

[Frank Klemm]

Code --------------------------------------------

#include <math.h>

double  TEST_RUN ( unsigned int ms )
{
    static float           A [1000];
    int                    ret = 0;
    size_t                 i;

    ms *= 1000;
    while ( ms-- ) {
        for ( i = 0; i < 1000; i++ )
            ret += (int) floorf (A[i]);                     <------------
    }

    return (double) ret;
}


Warning while compiling -------------------------------

test-0003-inc.c: In function 'test_0003_run':
test-0003-inc.c:12: warning: passing arg 1 of 'floorf' as 'float' rather than 'double' due to prototype
test-0003-inc.c:12: warning: cast does not match function type


Remarks ------------------------------------------------

Warning 1 is not very useful, it is so little useful so that it disturbs.
Warning 2 I do not understand.

-- 
Frank Klemm

Re: Strange Warnings

[Zack Weinberg]

On Wed, Sep 19, 2001 at 10:37:58PM +0200, Frank Klemm wrote:
> 
> test-0003-inc.c: In function 'test_0003_run':
> test-0003-inc.c:12: warning: passing arg 1 of 'floorf' as 'float' rather than 'double' due to prototype

Don't use -Wconversion.  It is only useful for shakedown compiles
after converting an old K+R program to ANSI prototypes.

> test-0003-inc.c:12: warning: cast does not match function type

What switch did you use to get this warning?

zw

Strange warnings

[Ryszard Kabatek]

In the sample below the class X should have a standard constructor
generated by the compiler. But I get the following warnings:

# eg++ x.cc
x.cc:6: warning: `class X' only defines private constructors and has no
friends
x.cc: In function `static class X * X::create()':
x.cc:5: no matching function for call to `X::X ()'
x.cc:3: candidates are: X::X(const X &)


The first warning I get too if I define a private standard constructor.
But there is a static function, that creates new instances of X,
class X does not need friend functions or classes.


# cat x.cc

class X {
    X(const X&);
  public:
    static X* create() {return new X();}
};

int main(int argc, char* argv)
{
  X* p = X::create();
  delete p;
}


Ryszard Kabatek
Martin-Luther University Halle-Wittenberg, Department of Physical Chemistry
Geusaer Str. 88, 06217 Merseburg, Germany
Tel. +49 3461 46 2487 Fax. +49 3461 46 2129

Re: Strange warnings

[Gabriel Dos_Reis]

Ryszard Kabatek <rysio@rumcajs.chemie.uni-halle.de> writes:

| In the sample below the class X should have a standard constructor
| generated by the compiler. But I get the following warnings:
| 
| # eg++ x.cc
| x.cc:6: warning: `class X' only defines private constructors and has no
| friends
| x.cc: In function `static class X * X::create()':
| x.cc:5: no matching function for call to `X::X ()'
| x.cc:3: candidates are: X::X(const X &)

EGCS gets it right. The Standard says:

12.1/5
---
  A default constructor for a class X is a constructor of class X that 
  can be called without an argument. If there is no user-defined
  constructor for class X, a default constructor is implicitly
  declared ...
---

Since you declared X::X(const X&), the default constructor is not
implicitly declared and it is up to you do so and give it a semantic.


| The first warning I get too if I define a private standard constructor.
| But there is a static function, that creates new instances of X,
| class X does not need friend functions or classes.

It is two way :-) : it can be helpful and quite inappropriate.

-- Gaby

Re: Strange warnings

[Gabriel Dos_Reis]

Ryszard Kabatek <rysio@rumcajs.chemie.uni-halle.de> writes:

| In the sample below the class X should have a standard constructor
| generated by the compiler. But I get the following warnings:
| 
| # eg++ x.cc
| x.cc:6: warning: `class X' only defines private constructors and has no
| friends
| x.cc: In function `static class X * X::create()':
| x.cc:5: no matching function for call to `X::X ()'
| x.cc:3: candidates are: X::X(const X &)

EGCS gets it right. The Standard says:

12.1/5
---
  A default constructor for a class X is a constructor of class X that 
  can be called without an argument. If there is no user-defined
  constructor for class X, a default constructor is implicitly
  declared ...
---

Since you declared X::X(const X&), the default constructor is not
implicitly declared and it is up to you do so and give it a semantic.


| The first warning I get too if I define a private standard constructor.
| But there is a static function, that creates new instances of X,
| class X does not need friend functions or classes.

It is two way :-) : it can be helpful and quite inappropriate.

-- Gaby

Strange warnings

[Ryszard Kabatek]

In the sample below the class X should have a standard constructor
generated by the compiler. But I get the following warnings:

# eg++ x.cc
x.cc:6: warning: `class X' only defines private constructors and has no
friends
x.cc: In function `static class X * X::create()':
x.cc:5: no matching function for call to `X::X ()'
x.cc:3: candidates are: X::X(const X &)


The first warning I get too if I define a private standard constructor.
But there is a static function, that creates new instances of X,
class X does not need friend functions or classes.


# cat x.cc

class X {
    X(const X&);
  public:
    static X* create() {return new X();}
};

int main(int argc, char* argv)
{
  X* p = X::create();
  delete p;
}


Ryszard Kabatek
Martin-Luther University Halle-Wittenberg, Department of Physical Chemistry
Geusaer Str. 88, 06217 Merseburg, Germany
Tel. +49 3461 46 2487 Fax. +49 3461 46 2129

Strange Warnings...

[Sebastian Ritterbusch]

Do the egcs (-O3 -g -Wall -Winline) warnings 

interval.inl:4: warning: \x03lass real * this' might be used
uninitialized in this function
interval.inl:4: warning: variable \x03lass real * this' might be clobbered by
\fongjmp' or \x16fork'

mean that i am in trouble?

interval.inl:
    3 inline interval::interval(const real &a,const real &b)
    4 {
    5    inf=a,sup=b;
    6 }
   
(class real is the same as double, its only data is a double)

How could *this ever be uninitialized in a member function? 

(This warning appears also in different member functions not only in 
constructors...)

I hope this really is a problem of the compiler... 

Ciao, Sebastian.