Make one specific target in Makefile tree - makefile

Question

I'm building Syslinux and there is one specific directory that I would like a different CC for. Instead of patching the Makefile, I can't I just invoke make with special arguments for that file? I haven't figured out how to do this.
When I just run make normally, this last lines are:
make -r -C lzo SRC="/syslinux-6.03/lzo" OBJ="/syslinux-6.03/bios/lzo" \
-f /syslinux-6.03/lzo/Makefile all
make[3]: Entering directory '/syslinux-6.03/bios/lzo'
gcc -o prepcore prepcore.o lzo.a
But if I cd into bios/lzo and run make prepcore, it doesn't work, probably because it needs some environment from the parent directory Makefiles. The error message is:
make: Entering directory '/syslinux-6.03/lzo'
/syslinux-6.03/lzo/Makefile:14: /build.mk: No such file or directory
make: *** No rule to make target '/build.mk'. Stop.
make: Leaving directory '/syslinux-6.03/lzo'
So my question is, what is the correct way of telling make "for the current directory tree, find a target for <file> and make it"?

Answer 1

Here is how to do this with remake. You run "remake" and set a breakpoint on the target you want to change. Then use the remake's "write" command to write the commands it would run to a shell script. Then you can edit that shell script to adjust the commands it runs for changes you want. The shell script will have a change directory command in it that you probably want to comment out.
Here is an example:
$ rm job.o
$ remake -X job.o
GNU Make 4.1+dbg0.91
Built for x86_64-unknown-linux-gnu
...
-> (/src/external-vcs/github/remake/Makefile:621)
Makefile: Makefile.in config.status
remake<0> s
... # Step until job.o
remake<9> s
Must remake target 'job.o'.
Makefile:781: update target 'job.o' due to: job.c /usr/include/stdc-predef.h ...
##>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
depbase=`echo job.o | sed 's|[^/]*$|.deps/&|;s|\.o$||'`;\
gcc -DLOCALEDIR=\"/usr/local/share/locale\" -DLIBDIR=\"/usr/local/lib\" -DINCLUDEDIR=\"/usr/local/include\" -DHAVE_CONFIG_H -I. -DMAKE_MAINTAINER_MODE -pthread -I/usr/include/guile/2.0 -Wall -Wextra -Wdeclaration-after-statement -Wshadow -Wpointer-arith -Wbad-function-cast -g -O2 -MT job.o -MD -MP -MF $depbase.Tpo -c -o job.o job.c &&\
mv -f $depbase.Tpo $depbase.Po
##<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
++ (/src/external-vcs/github/remake/.deps/job.Po:1)
job.o
remake<10> w
File "/tmp/job.o.sh" written.
remake<11>
Now look at the file it wrote:
#!/bin/bash
#/tmp/github/remake/.deps/job.Po:1
#cd /tmp/remake
depbase=`echo job.o | sed 's|[^/]*$|.deps/&|;s|\.o$||'`;\
gcc -DLOCALEDIR=\"/usr/local/share/locale\" -DLIBDIR=\"/usr/local/lib\" -DINCLUDEDIR=\"/usr/local/include\" -DHAVE_CONFIG_H -I. -DMAKE_MAINTAINER_MODE -pthread -I/usr/include/guile/2.0 -Wall -Wextra -Wdeclaration-after-statement -Wshadow -Wpointer-arith -Wbad-function-cast -g -O2 -MT job.o -MD -MP -MF $depbase.Tpo -c -o job.o job.c &&\
mv -f $depbase.Tpo $depbase.Po