libgcc: move gcc library linking to ldlibs_common

* move the '-lgcc' from ldlib_so to ldlibs_common and use ldlibs_common
  also for qmake (as done by the other build systems)
* remove unnecessary libgcc locating code for qmake

issue genodelabs#68

share/goa/lib/build/qmake.tcl

@@ -45,19 +45,11 @@ proc create_or_update_build_dir { } {
 	append qmake_cflags "-I$build_dir/qmake_root/include/QtCore/spec/$qmake_platform"
 
 	set qmake_ldlibs { }
-	lappend qmake_ldlibs -nostdlib
-	lappend qmake_ldlibs -L$abi_dir
 	lappend qmake_ldlibs -l:libc.lib.so
 	lappend qmake_ldlibs -l:libm.lib.so
 	lappend qmake_ldlibs -l:stdcxx.lib.so
 	lappend qmake_ldlibs -l:qt5_component.lib.so
 
-	if {$arch == "x86_64"} {
-		lappend qmake_ldlibs [file normalize [exec $cross_dev_prefix\gcc -m64 -print-libgcc-file-name]]
-	} else {
-		lappend qmake_ldlibs [file normalize [exec $cross_dev_prefix\gcc -print-libgcc-file-name]]
-	}
-
 	set ::env(GENODE_QMAKE_CC)           "${cross_dev_prefix}gcc"
 	set ::env(GENODE_QMAKE_CXX)          "${cross_dev_prefix}g++"
 	set ::env(GENODE_QMAKE_LINK)         "${cross_dev_prefix}g++"
@@ -66,8 +58,8 @@ proc create_or_update_build_dir { } {
 	set ::env(GENODE_QMAKE_NM)           "${cross_dev_prefix}nm"
 	set ::env(GENODE_QMAKE_STRIP)        "${cross_dev_prefix}strip"
 	set ::env(GENODE_QMAKE_CFLAGS)       "$qmake_cflags"
-	set ::env(GENODE_QMAKE_LFLAGS_APP)   "-nostdlib $ldflags $ldlibs_exe $qmake_ldlibs"
-	set ::env(GENODE_QMAKE_LFLAGS_SHLIB) "-nostdlib $ldflags_so $ldlibs_common $ldlibs_so $qmake_ldlibs"
+	set ::env(GENODE_QMAKE_LFLAGS_APP)   "$ldflags $ldlibs_common $ldlibs_exe $qmake_ldlibs"
+	set ::env(GENODE_QMAKE_LFLAGS_SHLIB) "$ldflags_so $ldlibs_common $ldlibs_so $qmake_ldlibs"
 
 
 	set qt_conf "qmake_root/mkspecs/$qmake_platform/qt.conf"

share/goa/lib/flags.tcl

@@ -87,6 +87,7 @@ lappend ldflags -Wl,-Ttext=0x01000000
 set     ldlibs_common { }
 lappend ldlibs_common -nostartfiles -nodefaultlibs -static-libgcc
 lappend ldlibs_common -L$abi_dir
+lappend ldlibs_common -Wl,--whole-archive -lgcc -Wl,--no-whole-archive
 
 set     ldlibs_exe    { }
 lappend ldlibs_exe   -Wl,--dynamic-linker=ld.lib.so
@@ -99,7 +100,7 @@ lappend ldlibs_exe    -T [file join $ld_script_dir genode_dyn.ld]
 
 set     ldlibs_so     { }
 lappend ldlibs_so     -Wl,-shared
-lappend ldlibs_so     -Wl,--whole-archive -lgcc -l:ldso_so_support.lib.a -Wl,--no-whole-archive
+lappend ldlibs_so     -Wl,--whole-archive -l:ldso_so_support.lib.a -Wl,--no-whole-archive
 lappend ldlibs_so     -T [file join $ld_script_dir genode_rel.ld]
 
 # determine ABIs to link against the executable