builtin: fix for tcc builds on paths with spaces on linux

Author: spytheman

vlib/builtin/builtin_d_gcboehm.c.v

@@ -51,13 +51,17 @@ $if dynamic_boehm ? {
 			#flag @VEXEROOT/thirdparty/libgc/gc.o
 		} $else {
 			$if !use_bundled_libgc ? {
-				#flag -L@VEXEROOT/thirdparty/tcc/lib
-				#flag -lgc
-				$if tinyc {
-					// this is a problem for compiler paths, containing spaces and commas, but tcc does not support -Xlinker :-|
-					#flag -Wl,-rpath,"@VEXEROOT/thirdparty/tcc/lib"
+				$if macos {
+					#flag -L@VEXEROOT/thirdparty/tcc/lib
+					#flag -lgc
+					$if tinyc {
+						// this is a problem for compiler paths, containing spaces and commas, but tcc does not support -Xlinker :-|
+						#flag -Wl,-rpath,"@VEXEROOT/thirdparty/tcc/lib"
+					} $else {
+						#flag -Xlinker -rpath -Xlinker "@VEXEROOT/thirdparty/tcc/lib"
+					}
 				} $else {
-					#flag -Xlinker -rpath -Xlinker "@VEXEROOT/thirdparty/tcc/lib"
+					#flag @VEXEROOT/thirdparty/tcc/lib/libgc.a
 				}
 			}
 		}