Frederic <fxx7792@cobalt.njit.edu>,
In a message on Thu, 26 Jun 2003 17:06:16 -0400, wrote :
F> Hi, all,
F>
F> I am modifying a big program written by somebody else.
F> When I modified some ".h" files, say a.h, then I run "make all", but I
F> found out make didn't recompile those files which included "a.h" file. In
F> my case "a.h" has some inline functions, so I have to manually remove
F> those .o files in order to get a fresh incremental build.
F>
F> My question is: is this phenomenon caused by bad-wrritten make files or I
F> misunderstood the functionality of make? Thanks.
It is bad written make files. 'Make' is not super human, you need to
list *all* of the dependencies.
There are two options:
1) *Manually* listing all of the .h files:
foo.o : foo.c a.h b.h c.h ...
2) Use the c preprocessor to generate the header dependencies:
Typical makefile fragment:
HEADERS = Character.h Record.h Dice.h Monster.h Spells.h Dressings.h Space.h
LSRCS = Character.cc Dice.cc Monster.cc Spells.cc Dressings.cc Space.cc
CXX = c++
BaseCXXFLAGS = -g -O2
DEFS = -DSTDC_HEADERS=1 -DSIZEOF_LONG=4 -DSIZEOF_INT=4 -DHAVE_BOOL=1
SHLIB_CFLAGS = -fPIC
INCLUDES = -I.
CXXFLAGS = $(DEFS) $(BaseCXXFLAGS) $(SHLIB_CFLAGS) $(INCLUDES) -c -Wall
# other defs and rules ommited
# Make sure some target depends on .depend (I usually include .depend on
# the 'all' target).
..depend: $(LSRCS) $(HEADERS)
$(CXX) -M $(CXXFLAGS) $(LSRCS) > .depend
#
# include a dependency file if one exists
#
ifeq (.depend,$(wildcard .depend))
include .depend
endif
man gcc (-M):
-M [ -MG ]
Tell the preprocessor to output a rule suitable for
make describing the dependencies of each object
file. For each source file, the preprocessor out<AD>
puts one make-rule whose target is the object file
name for that source file and whose dependencies
are all the files `#include'd in it. This rule may
be a single line or may be continued with `\'-new<AD>
line if it is long. The list of rules is printed
on standard output instead of the preprocessed C
program.
`-M' implies `-E'.
`-MG' says to treat missing header files as gener<AD>
ated files and assume they live in the same direc<AD>
tory as the source file. It must be specified in
addition to `-M'.
F>
F> ================================================== =============================================
F> |Frederic |
F> | |
F> |The road goes ever on and on. |
F> | - Bilbo Baggins |
F> ================================================== =============================================
F>
