gcc warning - Why does a "function name" evaluate to true in C and how to get warned on it -


i stumbled across following behaviour of gcc 3.2.2 writing c program:

in if statement forgot braces of function , wrote:

if(myfunc)... instead of if(myfunc())...

this did not generate error neither warning although have pretty every warning turned on.

it evaluated true. why writing legal code in first place ? because function exists/has address ? know how 1 avoid such mistakes or if there warning option overlooked ? issue better solved in later gcc versions ?

here exact compiler call completeness:

 msp430-gcc -g -os -mmcu=msp430x1611 -wall -w -wfloat-equal -wundef -wshadow -wpointer-arith -wbad-function-cast -wcast-qual -wwrite-strings -wsign-compare -waggregate-return -wstrict-prototypes -wmissing-prototypes -wmissing-declarations  -wredundant-decls -wnested-externs -wimplicit-function-declaration -werror

(since i'm forced use gcc 3.2.3 there no -wextra)

if (myfunc) equivalent if (&myfunc), you're testing address of function, of course non-zero, i.e. true.

with gcc 4.2.1 , -wall following warning:

myfunc.c:11: warning: address of ‘myfunc’ evaluate ‘true’


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