[plt-scheme] where is compiled/native/<arch>-<os>/3m/<filename>3m.c ?

I'm up and running, so I don't need help, I'm just curious what  
happened to one type of file in the compilation process.

I start with:

mzc -v --save-temps --debug --auto-dir ++ldf /opt/local/lib/mysql5/ 
mysql/libmysqlclient.dylib ++cppf -I/opt/local/include/mysql5/mysql + 
+ccf -I/opt/local/include/mysql5/mysql mysqlclient.ss

which does this:

  [compiling native code to "./compiled/native/i386-macosx/3m/ 
mysqlclient.o"]
compile-extension: (/usr/bin/gcc -c -O2 -fPIC -fno-common -DOS_X - 
DMZ_PRECISE_GC -I/opt/local/include/mysql5/mysql -I/usr/local/plt/ 
collects/compiler -I/usr/local/plt/include ./compiled/native/i386- 
macosx/3m/mysqlclient3m.c -o ./compiled/native/i386-macosx/3m/ 
mysqlclient.o)

which has a bunch of warnings like this I'm ignoring for the moment:

./compiled/native/i386-macosx/3m/mysqlclient3m.c: In function  
'mzc_cffi_2':
./compiled/native/i386-macosx/3m/mysqlclient3m.c:1474: warning:  
assignment discards qualifiers from pointer target type

and which has an error I have to fix first:

./compiled/native/i386-macosx/3m/mysqlclient3m.c: In function  
'mzc_cffi_51':
./compiled/native/i386-macosx/3m/mysqlclient3m.c:3373: error: too few  
arguments to function 'mysql_shutdown'

The problem is there is no mysqlclient3m.c in that 3m directory, only  
mysqlclient.c.  Did mzc delete it after issuing the error message?  I  
hoped --save-temps would preserve it if it's just an intermediate  
file, so I could debug whatever's wrong.  Though the line numbers  
were different in mysqlclient.c, I was able to find the subroutine  
mzc_cffi_51 and figure out what was wrong.  I'm just curious where  
mysqlclient3m.c went.

I did find at the top (in the directory where compiled/ sits) the  
files:  mysqlclient3m.i mysqlclient3m.s