I posted a similar email to the fpc-pascal mailing list, but I am guessing that since the issue is somewhat complex, someone on this list might have a better understanding of what the underlying issue might be.

I have successfully ported a Delphi DLL to a compiled shared library under 32-bit linux using free pascal, and it works wonderfully. Yesterday, I decided to try and port it over to the x86_64 architecture on linux.

For the most part, everything went smoothly - there was a small issue which I resolved using PtrInt instead of integer, and all units now compile.

The problem arises when the linker attempts to put all the pieces together into one .so :

/usr/bin/ld: uCUNASP_CLCalc.o: relocation R_X86_64_32S against `U_UCUNASP_CLCALC_CUNASPCLSET' can not be used when making a shared object; recompile with -fPIC
uCUNASP_CLCalc.o: could not read symbols: Bad value

I have successfully created a shared library, so it is not an -fPIC issue (I think, and am compiling with the -Cg flag as well).

The CUNASPCLSET refers to a public unit-wide variable (a custom record type). If I redeclare the record type as an object and dynamically create the variable in the unit's initialization section (and free it up on finalization), then the error disappears, and a similar issue pops up with another record type in a different unit - I have also seen a similar error appear with a unit level array [0..10] of double.

Again - the code works fine on 32-bit linux, but not for x86_64. Does anyone have any ideas?

Thanks much,
Alan Krause

It's a bug in the compiler. Please submit a bug report with a compilable sample that demonstrates the problem.

Jonas

Jonas Maebe wrote

It's a bug in the compiler. Please submit a bug report with a compilable sample that demonstrates the problem.

Jonas,

Thanks much for the reply. I will submit a bug report ASAP. I spent most of the morning trying to simplify the error case, and came up with the following:

---

library project1;
uses
Classes;
function dRound(iDec: integer; dRate: double): double;
const
   TenToPower: Array[0..9] of integer = (1, 10, 100, 1000, 10000, 100000,
                                         1000000, 10000000, 100000000,
1000000000);
var
   dInc : double;
begin
   if iDec > 0 then begin
      dInc := 0.5000001;
      result := trunc (dRate * (TenToPower [iDec]) + dInc) /
         TenToPower [iDec];
   end else begin
      result := dRate;
   end ;
end;
function one : double; cdecl;
begin
   Result := dRound( 2, 0.529 ) ;
end;

---

Trying to compile this under fpc 2.1.4 on x86_64 via "fpc -Sd proj.pas" gives me the following results:

Compiling proj.pas
Linking libproj.so
/usr/bin/ld: proj.o: relocation R_X86_64_32S against `TC_P$PROJECT1_DROUND$LONGINT$TROUNDTYPE$DOUBLE$$DOUBLE_TENTOPOWER' can not be used when making a shared object; recompile with -fPIC proj.o: could not read symbols: Bad value

I'll sign up for an account and post the ticket now.

Thanks much,
Alan