Re: [PATCH 2/4] Makefile: Replace explicit subdir rules with pattern rules

[Pedro Alves <palves at redhat dot com>]

On 11/15/2016 06:00 PM, Simon Marchi wrote:
> On 2016-11-15 12:54, Pedro Alves wrote:
>> On 11/13/2016 03:46 AM, Simon Marchi wrote:
>>>  # Need to explicitly specify the compile rule as make will do nothing
>>>  # or try to compile the object file into the sub-directory.
>>
>> Do these comments need adjustment?
> 
> I thought they were still true and relevant after the change.  What do
> you think?

But should we at least merge them?  Looking at your branch on github,
we end up with:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

#
# gdb/cli/ dependencies
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the sub-directory.

%.o: $(srcdir)/cli/%.c
	$(COMPILE) $<
	$(POSTCOMPILE)

# GCC Compile support dependencies
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the sub-directory.

%.o: $(srcdir)/compile/%.c
	$(COMPILE) $<
	$(POSTCOMPILE)

#
# GDBTK sub-directory
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the mi directory.

all-gdbtk: insight$(EXEEXT)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


The last one is strange, for talking about MI.


And then a bit further below, we have the same comment several
times again:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

#
# gdb/mi/ dependencies
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the sub-directory.

%.o: $(srcdir)/mi/%.c
	$(COMPILE) $<

# gdb/common/ dependencies
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the sub-directory.

%.o: ${srcdir}/common/%.c
	$(COMPILE) $<
	$(POSTCOMPILE)

common-agent.o: $(srcdir)/common/agent.c
	$(COMPILE) $(srcdir)/common/agent.c
	$(POSTCOMPILE)

#
# gdb/target/ dependencies
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the sub-directory.

%.o: ${srcdir}/target/%.c
	$(COMPILE) $<
	$(POSTCOMPILE)

#
# gdb/arch/ dependencies
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the sub-directory.

%.o: ${srcdir}/arch/%.c
	$(COMPILE) $<
	$(POSTCOMPILE)

# gdb/nat/ dependencies
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the sub-directory.

%.o: ${srcdir}/nat/%.c
	$(COMPILE) $<
	$(POSTCOMPILE)

#
# gdb/tui/ dependencies
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the sub-directory.

%.o: $(srcdir)/tui/%.c
	$(COMPILE) $<
	$(POSTCOMPILE)

# gdb/guile dependencies
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the sub-directory.

%.o: $(srcdir)/guile/%.c
	$(COMPILE) $<
	$(POSTCOMPILE)

# gdb/python/ dependencies
#
# Need to explicitly specify the compile rule as make will do nothing
# or try to compile the object file into the sub-directory.

# Flags needed to compile Python code
PYTHON_CFLAGS=@PYTHON_CFLAGS@

%.o: $(srcdir)/python/%.c
	$(COMPILE) $(PYTHON_CFLAGS) $<
	$(POSTCOMPILE)

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


I think a single comment talking about needing a compile rule for
each subdir, might be clearer/simpler.

Also, the cases that are exceptions I think would benefit
from a comment, like e.g., the common-agent.o rule.

Thanks,
Pedro Alves