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A Problem with Invalid Conversion When Utilizing Malloc
Home Backend Development C++ Why Does Malloc Throw an \'Invalid Conversion from \'void\' to \'char\'\' Error in C ?

Why Does Malloc Throw an \'Invalid Conversion from \'void\' to \'char\'\' Error in C ?

Oct 29, 2024 am 12:02 AM

Why Does Malloc Throw an

A Problem with Invalid Conversion When Utilizing Malloc

In C , developers frequently encounter the error "invalid conversion from 'void' to 'char'" while utilizing malloc to allocate memory. This issue arises when there is an incorrect casting of the returned memory address from malloc().

In the code provided, the issue is addressed on line 5:

<code class="cpp">char *foo = malloc(1);</code>

To rectify this issue, it is essential to explicitly cast the return value of malloc() to the desired type. In this instance, the goal is to obtain a character pointer, so the correct line would be:

<code class="cpp">char *foo = (char*)malloc(1);</code>

By adding the necessary cast, the compiler is explicitly informed that the returned address from malloc() should be treated as a character pointer. This casting ensures that the memory address is appropriately assigned to the "foo" variable, resolving the conversion error.

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