- Cause of the
problem:
- The C colpiler made
an
implicit function
prototype assumption
- The implicit assumption was wrong value !!!
- The C colpiler made
an
implicit function
prototype assumption
- How to fix the
problem:
- Prevent
the C compiler
from making
the
implicit function prototype assumption
by:
- Specifying the function declaration !!!
Example:
File func3aOK.c File func3bOK.c double square ( double x ) { double r; // Local variable r = x * x; // Statement return ( r ); // Return }extern double square ( double ); int main( int argc, char *argv[] ) { double a, b; a = 4.0; b = square( a ); // Call square printf("Square of %lf = %lf\n", a, b); }
- Prevent
the C compiler
from making
the
implicit function prototype assumption
by:
- Example Program:
(Demo above code)
- Prog file func3aOK.c: click here
- Prog file func3bOK.c: click here
How to run the program:
- Right click on link and
save in a scratch directory
- To compile:
gcc -c func3aOK.c
gcc -c func3bOK.c
gcc func3aOK.o func3bOK.o - To run:
a.out
- You will now get the correct result !!!
Result:
Number = 4.000000 Number = 16.000000 (correct !)