diff --git a/build.sh b/build.sh
index ae3bc3d8..c751885c 100755
--- a/build.sh
+++ b/build.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 set -e
 
diff --git a/mkfiles/gcc.mak b/mkfiles/gcc.mak
index 96be88ab..8da8f45e 100644
--- a/mkfiles/gcc.mak
+++ b/mkfiles/gcc.mak
@@ -27,7 +27,7 @@ CFLAGS1 = -Os -Wall -Werror -Wno-pointer-to-int-cast -Wno-incompatible-pointer-t
 .SUFFIXES: .c .asm .com .exe .obj
 ifeq ($(UTILS_BUILD),1)
 .c.exe:
-	gcc -x c -Og -g -Wall -DGCC -D__GETOPT_H -I../suppl $< -o $@
+	gcc -x c -Og -g -Wall -DTARGET_USE_GCC_IA16 -D__GETOPT_H -I../suppl $< -o $@
 else ifeq ($(COMPACT_MODEL),1)
 .c.obj .c.exe:
 	@echo ------------------------------------------------------
diff --git a/mkfiles/watcom.mak b/mkfiles/watcom.mak
index 86393cf0..427a376e 100644
--- a/mkfiles/watcom.mak
+++ b/mkfiles/watcom.mak
@@ -36,7 +36,13 @@ CFLAGS1 = -os-s-wx
   $(CL) -ms -I$(WATCOM)$(DIRSEP)h $< -fm -fe=$@ -I..$(DIRSEP)suppl
 !  endif
 ! else ifdef __OSX__
-  clang -x c -Og -g -Wall -Wno-pragma-pack -DGCC -D__GETOPT_H -I../suppl $< -o $@
+  clang -x c -Og -g -Wall -Wno-pragma-pack -D__GETOPT_H -I../suppl $< -o $@
+! else ifdef __FREEBSD__
+  clang -x c -Og -g -Wall -Wno-pragma-pack -D__GETOPT_H -I../suppl $< -o $@
+! else ifdef __OPENBSD__
+  clang -x c -Og -g -Wall -Wno-pragma-pack -D__GETOPT_H -I../suppl $< -o $@
+! else ifdef __NETBSD__
+  gcc -x c -Og -g -Wall -Wno-pragma-pack -D__GETOPT_H -I../suppl $< -o $@
 ! else
   $(CL386) -I$(WATCOM)$(DIRSEP)h $< -fm -fe=$@ -I..$(DIRSEP)suppl
 ! endif
diff --git a/tools/ptchsize.c b/tools/ptchsize.c
index dd7866ac..c86633b4 100644
--- a/tools/ptchsize.c
+++ b/tools/ptchsize.c
@@ -230,7 +230,7 @@ int main(int argc, char **argv)
 	}
 
 	if(argc == 2
-#ifndef GCC
+#ifndef TARGET_USE_GCC_IA16
 	   || ival.heapPos == ~0
 #endif
 	   ) {
@@ -275,7 +275,7 @@ int main(int argc, char **argv)
 	 , argv[1], tosize);
 	/* Watcom already has extraMin minimal and dynamically adjusts its MCB*/
 	if(tosize) {
-#ifdef GCC
+#ifdef TARGET_USE_GCC_IA16
 		/* need to adjust SP */
 		unsigned startbss = 0x10000 - exe.extraMax * 16;
 		exe.fSP = startbss + ival.extraSpace * 16 + tosize;
@@ -293,7 +293,7 @@ int main(int argc, char **argv)
 		return 77;
 	}
 
-#ifndef GCC
+#ifndef TARGET_USE_GCC_IA16
 	if(fseek(freecom, ival.heapPos, SEEK_SET) != 0) {
 		printf("Failed to seek to heap size offset in %s\n", argv[1]);
 		return 42;
diff --git a/utils/mkinfres.c b/utils/mkinfres.c
index 7eb6842a..9eabe540 100644
--- a/utils/mkinfres.c
+++ b/utils/mkinfres.c
@@ -130,7 +130,7 @@ int addImageDisplacement(const char * const fnam
 		*extraSpace += (stacksize+15)/16;
 	}
 	fclose(f);
-#ifdef GCC
+#ifdef TARGET_USE_GCC_IA16
 	stacksize = 4*1024;
 	*extraSpace += stacksize / 16;
 #else