lang/fpc: Restore DragonFly support

FPC cannot use the gold linker.  Gold requires that the linker script have
the --script flag passed, but doing so will break FreePascal (the flags
causes the internal linker to be bypassed).  Since DragonFly switches
linkers through the environment and it's not clear how to set that, I've
hardcoded the linker path for DragonFly for now.  Also, we must avoid using
Gold for the bootstrap compiler (which has not been hardcoded) so passing
LDVER=ld.bfd during the bootstrap stage is necessary to guarantee this.
FreeBSD doesn't use this variable so its harmless on that OPSYS.

The other major fix was fixing the dirent record which differs on DragonFly.
This is why unit searching has always failed.

All patches will be submitted upstream.  This should be a no-op for FreeBSD,
thus no bump.

lang/fpc/Makefile

@@ -115,7 +115,7 @@ do-build:
 # build fpc compiler
 	@${ECHO_MSG} "##### STARTING COMPILER #####"
 	(cd ${WRKDIR}/${FPCSRCDIR}/compiler && ${SETENV} ${MAKE_ENV} \
-		${MAKE_CMD} cycle ${MAKE_ARGS} ${BOOTPPC})
+		LDVER=ld.bfd ${MAKE_CMD} cycle ${MAKE_ARGS} ${BOOTPPC})
 	@${ECHO_MSG} "##### COMPLETE COMPILER #####"
 
 # build fpcmkcfg

lang/fpc/files/patch-compiler_cfileutl.pas

@@ -0,0 +1,12 @@
+--- compiler/cfileutl.pas.orig	2015-11-13 21:15:29 UTC
++++ compiler/cfileutl.pas
+@@ -23,9 +23,7 @@ unit cfileutl;
+ 
+ {$i fpcdefs.inc}
+ 
+-{$ifndef DragonFly}
+ {$define usedircache}
+-{$endif DragonFly}
+ 
+ interface
+ 

lang/fpc/files/patch-compiler_systems_t__bsd.pas

@@ -0,0 +1,23 @@
+--- compiler/systems/t_bsd.pas.orig	2015-11-13 21:15:29 UTC
++++ compiler/systems/t_bsd.pas
+@@ -192,6 +192,8 @@ begin
+       DynamicLinker:='/usr/libexec/ld.so'
+      else if target_info.system in systems_netbsd then
+       DynamicLinker:='/usr/libexec/ld.elf_so'
++     else if target_info.system=system_x86_64_dragonfly then
++      DynamicLinker:='/libexec/ld-elf.so.2'
+      else
+        DynamicLinker:='';
+    end;
+@@ -718,7 +720,10 @@ begin
+   Replace(cmdstr,'$DYNLINK',DynLinkStr);
+   if (target_info.system in systems_darwin) then
+     Replace(cmdstr,'$PRTOBJ',GetDarwinPrtobjName(false));
+-  BinStr:=FindUtil(utilsprefix+BinStr);
++  if target_info.system=system_x86_64_dragonfly then
++     BinStr:='/usr/libexec/binutils225/elf/ld.bfd'
++  else
++     BinStr:=FindUtil(utilsprefix+BinStr);
+ 
+   { create dsym file? }
+   extdbgbinstr:='';

lang/fpc/files/patch-rtl_bsd_ossysc.inc

@@ -0,0 +1,14 @@
+--- rtl/bsd/ossysc.inc.orig	2015-11-13 21:15:29 UTC
++++ rtl/bsd/ossysc.inc
+@@ -282,7 +282,11 @@ begin
+  repeat
+   novalid:=false;
+   CurEntry:=pdirent(dirp^.dd_rewind);
++{$ifdef dragonfly}
++  RecLen:=(CurEntry^.d_namlen + 24) and $FFFFFFF8;
++{$else}
+   RecLen:=CurEntry^.d_reclen;
++{$endif}
+   if RecLen<>0 Then
+    begin {valid direntry?}
+     if CurEntry^.d_fileno<>0 then

lang/fpc/files/patch-rtl_bsd_ostypes.inc

@@ -0,0 +1,27 @@
+--- rtl/bsd/ostypes.inc.orig	2015-11-13 21:15:29 UTC
++++ rtl/bsd/ostypes.inc
+@@ -145,6 +145,16 @@ TYPE
+ 
+   { directory services }
+ {$ifndef darwinarm}
++{$ifdef dragonfly}
++   dirent  = record
++        d_fileno      : ino_t;                          // file number of entry
++        d_namlen      : cuint16;                        // strlen (d_name)
++        d_type        : cuint8;                         // file type, see below
++        d_unused1     : cuint8;                         // padding, reserved
++        d_unused2     : cuint32;                        // reserved
++        d_name        : array[0..255] of char;          // name, null terminated
++   end;
++{$else}
+    dirent  = record
+         d_fileno      : cuint32;                        // file number of entry
+         d_reclen      : cuint16;                        // length of this record
+@@ -152,6 +162,7 @@ TYPE
+         d_namlen      : cuint8;                         // length of string in d_name
+         d_name        : array[0..(255 + 1)-1] of char;  // name must be no longer than this
+    end;
++{$endif}
+ {$else not darwinarm}
+    {$packrecords 4}
+    { available on Mac OS X 10.6 and later, and used by all iPhoneOS versions }