Respect build environment settings

Bug: https://bugs.gentoo.org/913186
Bug: https://bugs.gentoo.org/913188
Bug: https://bugs.gentoo.org/913189


--- a/CPP/7zip/7zip_gcc.mak
+++ b/CPP/7zip/7zip_gcc.mak
@@ -103,14 +103,14 @@ SHARED_EXT=.dll
 LDFLAGS = -shared -DEF $(DEF_FILE) $(LDFLAGS_STATIC)
 else
 SHARED_EXT=.so
-LDFLAGS = -shared -fPIC $(LDFLAGS_STATIC)
+LDFLAGS = -shared -fPIC $(G_LDFLAGS) $(LDFLAGS_STATIC)
 CC_SHARED=-fPIC
 endif


 else

-LDFLAGS = $(LDFLAGS_STATIC)
+LDFLAGS = $(LDFLAGS_STATIC) $(G_LDFLAGS)
 # -z force-bti
 # -s is not required for clang, do we need it for GCC ???

@@ -169,7 +169,7 @@ endif



-CFLAGS = $(MY_ARCH_2) $(LOCAL_FLAGS) $(CFLAGS_BASE2) $(CFLAGS_BASE) $(FLAGS_FLTO) $(CC_SHARED) -o $@
+CFLAGS = $(MY_ARCH_2) $(LOCAL_FLAGS) $(CFLAGS_BASE2) $(CFLAGS_BASE) $(FLAGS_FLTO) $(CC_SHARED) $(G_CFLAGS) -o $@


 ifdef IS_MINGW
@@ -209,7 +209,7 @@ CXX_WARN_FLAGS =
 #-Wno-invalid-offsetof
 #-Wno-reorder

-CXXFLAGS = $(MY_ARCH_2) $(LOCAL_FLAGS) $(CXXFLAGS_BASE2) $(CFLAGS_BASE) $(FLAGS_FLTO) $(CXXFLAGS_EXTRA) $(CC_SHARED) $(CXX_WARN_FLAGS) $(CXX_STD_FLAGS) $(CXX_INCLUDE_FLAGS) -o $@
+CXXFLAGS = $(MY_ARCH_2) $(LOCAL_FLAGS) $(CXXFLAGS_BASE2) $(CFLAGS_BASE) $(FLAGS_FLTO) $(CXXFLAGS_EXTRA) $(CC_SHARED) $(CXX_WARN_FLAGS) $(CXX_STD_FLAGS) $(CXX_INCLUDE_FLAGS) $(G_CXXFLAGS) -o $@

 STATIC_TARGET=
 ifdef COMPL_STATIC