问题
I need to run an old FORTRAN IV code I was given (which is supposed to run just fine). I downloaded a trial version of Intel compiler and tried to compile the source file I was given with the command:
ifort -f66 abel.for -o mycode
where abel.for is the name of the source file. I got a bunch of warnings and errors. I wanted to ask about the first warning I was given:
The number of arguments is incompatible with intrinsinc procedure, assume 'external'. [KNOT]
where KNOT is a function defined as:
C AAOK0162
C PROCEDURE FOR LOCATING THE SPLINE SECTION TO WHICH AN AAOK0163
C ARGUMENT BELONGS. AAOK0164
C N NUMBER OF KNOTS IN THE SPLINE REPRESENTATION AAOK0165
C U KNOTS POSITION AAOK0166
C X THE ARGUMENT WHOSE SPLINE SECTION IS SOUGHT AAOK0167
C I THE NUMBER OF THE SMALLEST KNOT LARGER THAN X AAOK0168
C AAOK0169
INTEGER FUNCTION KNOT(N,U,X) AAOK0170
IMPLICIT REAL*8(A-H,O-Z) AAOK0171
DIMENSION U(1) AAOK0172
C TEST WHETHER POINT IN RANGE AAOK0173
IF (X.LT.U(1)) GOTO 990 AAOK0174
IF (X.GT.U(N)) GOTO 990 AAOK0175
C ESTIMATE KNOT INTERVAL BY ASSUMING EQUALLY SPACED KNOTS AAOK0176
J=DABS(X-U(1))/(U(N)-U(1))*(N-1)+1 AAOK0177
C ENSURE CASE X=U(N) GIVES J=N-1 AAOK0178
J=MIN0(J,N-1) AAOK0179
C SEARCH FOR KNOT INTERVAL CONTAINING X AAOK0180
IF (X.GE.U(J)) GOTO 11 AAOK0181
2 J=J-1 AAOK0182
IF(X.LT.U(J)) GOTO 2 AAOK0183
GOTO 7 AAOK0184
1 J=J+1 AAOK0185
11 IF(X.GT.U(J+1)) GOTO 1 AAOK0186
7 KNOT=J+1 AAOK0187
RETURN AAOK0188
990 KNOT=-1 AAOK0189
RETURN AAOK0190
END AAOK0191
and the compiler error indicates the call of this function from a subsequent subroutine (line AAOK0211):
SUBROUTINE ABEL1(N,IN,X,XN,A,B,C,D,YCALC) AAOK0201
IMPLICIT REAL*8 (A-H,O-Z) AAOK0202
DIMENSION X(1),XN(1),A(1),B(1),C(1),D(1),YCALC(1) AAOK0203
COMMON /R/ R AAOK0204
COMMON /PI/ PI AAOK0205
DO 70 L=1,IN AAOK0206
R=X(L) AAOK0207
IF(R.EQ.0.D0) R=1.D-6 AAOK0208
YCALC(L)=0.D0 AAOK0209
IF (R.EQ.XN(N+1)) R=R-1.D-6 AAOK0210
I=KNOT(N+1,XN,R) AAOK0211
IF(I.EQ.-1) GOTO 70 AAOK0212
IF(I.EQ.N+1) GOTO 99 AAOK0213
DO 60 K=I,N AAOK0214
X1=XN(K) AAOK0215
X2=XN(K+1) AAOK0216
S=3.D0*A(K)*DI1(2,X1,X2)+2.D0*B(K)*DI1(1,X1,X2)+C(K)*DI1(0,X1,X2) AAOK0217
YCALC(L)=YCALC(L)+S AAOK0218
60 CONTINUE AAOK0219
99 X2=XN(I) AAOK0220
S=3.D0*A(I-1)*DI1(2,R,X2)+2.D0*B(I-1)*DI1(1,R,X2) AAOK0221
* +C(I-1)*DI1(0,R,X2) AAOK0222
YCALC(L)=-(YCALC(L)+S)/PI AAOK0223
70 CONTINUE AAOK0224
RETURN AAOK0225
END AAOK0226
I wanted to ask what seems to cause this warning and if it is safe to just ignore it?
回答1:
KNOT() is a non-standard specific intrinsic function for the NOT function which accepts 8 byte integers (see https://docs.oracle.com/cd/E19422-01/819-3684/3_F77_Intrins.html ).
You can indeed ignore the warning in this case. Because the numbers and types of the arguments differ, the compiler will not call the intrinsic inadvertently, so it is safe. The problem would be if the compiler had a function which looks exactly the same but does something different. The external statement serves the purpose to prevent such collisions.
The thing you can do to suppress the warning is to tell the compiler you have your own external function KNOT() by placing
EXTERNAL *KNOT
in the declaration section of each compilation unit which calls KNOT, so for example,
SUBROUTINE ABEL1(N,IN,X,XN,A,B,C,D,YCALC)
IMPLICIT REAL*8 (A-H,O-Z)
EXTERNAL *KNOT
The type should be all-right given your implicit typing rules, but you can specify it explicitly by
INTEGER KNOT
Note: the * in EXTERNAL *KNOT means that not an intrinsic, but a user-supplied function should be used. This behaviour differs from modern Fortran! See http://h21007.www2.hp.com/portal/download/files/unprot/fortran/docs/lrm/lrm0633a.htm In FORTRAN 77 and later use just EXTERNAL KNOT.
来源：https://stackoverflow.com/questions/33012052/fixing-fortran-iv-warning-the-number-of-arguments-is-incompatible-with-intrins