Re: Best means to override CXXFLAGS locally

[Akim Demaille]

> What would be the cleanest means to handle this exception?

Here is what I did:
- Force automake to generate an object specific rule by
  using some foo_CXXFLAGS
- Open Makefile.in, get the specific rules.
- Use LTCOMPILECXX to factor the common part
- Append $(MY_NOPTION_CXXFLAGS) to it
- rename the (object) output file name Automake used
- include all this in the Makefile.am
- remove the foo_CXXFLAGS so that Automake do not
  produce a rule for this object
- and therefore my own rule is obeyed with conflict
- and finally pray for no significant changes in the
  future versions of Automake ;)

# This is an edited copy of Automake's compilation rule so that we can
# insert $(PARSER_CXXFLAGS) *after* $(CXXFLAGS) to override -O2.
# Using foo_CXXFLAGS does not suffice, since CXXFLAGS, a user
# variable, appears last.
ugrammar.lo: ugrammar.cc
@am__fastdepCXX_TRUE@	if $(LTCXXCOMPILE) $(PARSER_CXXFLAGS) -MT  
ugrammar.lo -MD -MP -MF "$(DEPDIR)/ugrammar.Tpo" -c -o ugrammar.lo  
`test -f 'ugrammar.cc' || echo '$(srcdir)/'`ugrammar.cc; \
@am__fastdepCXX_TRUE@	then mv -f "$(DEPDIR)/ugrammar.Tpo" "$(DEPDIR)/ 
ugrammar.Plo"; else rm -f "$(DEPDIR)/ugrammar.Tpo"; exit 1; fi
@AMDEP_TRUE@@am__fastdepCXX_FALSE@	source='ugrammar.cc'  
object='ugrammar.lo' libtool=yes @AMDEPBACKSLASH@
@AMDEP_TRUE@@am__fastdepCXX_FALSE@	DEPDIR=$(DEPDIR) $(CXXDEPMODE) $ 
(depcomp) @AMDEPBACKSLASH@
@am__fastdepCXX_FALSE@	$(LTCXXCOMPILE) $(PARSER_CXXFLAGS) -c -o  
ugrammar.lo `test -f 'ugrammar.cc' || echo '$(srcdir)/'`ugrammar.cc


Is there anything better to do?  Is there a trap I just fell in?