itk libdca libvpx openscenegraph: gcc 5 compatibility

src/itk.mk

@@ -16,6 +16,8 @@ define $(PKG)_UPDATE
 endef
 
 define $(PKG)_BUILD
+    $(SED) -i 's^#  error "Dunno about this gcc"^#  warning "Dunno about this gcc"^;' \
+        '$(1)/Modules/ThirdParty/VNL/src/vxl/vcl/vcl_compiler.h'
     mkdir '$(1).build'
     cd '$(1).build' && cmake \
         -DCMAKE_TOOLCHAIN_FILE='$(CMAKE_TOOLCHAIN_FILE)' \
@@ -25,6 +27,7 @@ define $(PKG)_BUILD
         -DBUILD_TESTING=FALSE \
         -DBUILD_EXAMPLES=FALSE \
         -DITK_USE_SYSTEM_HDF5=TRUE \
+        -DCMAKE_C_FLAGS='-std=gnu89' \
         '$(1)'
     $(MAKE) -C '$(1).build' -j '$(JOBS)' install VERBOSE=1
 endef

src/libdca.mk

@@ -17,7 +17,8 @@ endef
 
 define $(PKG)_BUILD
     cd '$(1)' && ./configure \
-        $(MXE_CONFIGURE_OPTS)
+        $(MXE_CONFIGURE_OPTS) \
+        CFLAGS='-std=gnu89'
     $(MAKE) -C '$(1)' -j '$(JOBS)' bin_PROGRAMS= sbin_PROGRAMS= noinst_PROGRAMS=
     $(MAKE) -C '$(1)' -j 1 install bin_PROGRAMS= sbin_PROGRAMS= noinst_PROGRAMS=
 

src/libvpx.mk

@@ -25,7 +25,8 @@ define $(PKG)_BUILD
         --target=@libvpx-target@ \
         --disable-examples \
         --disable-install-docs \
-        --as=$(TARGET)-yasm
+        --as=$(TARGET)-yasm \
+        --extra-cflags='-std=gnu89'
     $(MAKE) -C '$(1)' -j '$(JOBS)'
     $(MAKE) -C '$(1)' -j 1 install
     $(TARGET)-ranlib $(PREFIX)/$(TARGET)/lib/libvpx.a

src/openscenegraph.mk

@@ -22,7 +22,7 @@ define $(PKG)_BUILD
     mkdir '$(1).build'
     cd '$(1).build' && cmake '$(1)' \
         -DCMAKE_TOOLCHAIN_FILE='$(CMAKE_TOOLCHAIN_FILE)' \
-        -DCMAKE_CXX_FLAGS=-D__STDC_CONSTANT_MACROS \
+        -DCMAKE_CXX_FLAGS='-D__STDC_CONSTANT_MACROS -fpermissive' \
         -DCMAKE_HAVE_PTHREAD_H=OFF \
         -DPKG_CONFIG_EXECUTABLE='$(PREFIX)/bin/$(TARGET)-pkg-config' \
         -DDYNAMIC_OPENTHREADS=OFF \