m4 has an useful option --synclines that outputs #line lines to synchronize output. However, this option breaks C macro definition. Consider the following source file:

#define MACRO  blabla 
    ifelse(`', `', `dnl
    a 
    b 
    ', `dnl
    c 
    d 
    ') 
    /* */

It results in the following with --synclines:

+ /bin/bash -c 'm4 -sg test.m4'
#line 1 "test.m4"
#define MACRO  blabla 
                a 
#line 2
        b 
#line 2
         
#line 9
        /* */

And without synclines:

+ /bin/bash -c 'm4 -g test.m4'
#define MACRO  blabla 
                a 
        b 
         
        /* */

The resulting #line lines inside a macro definition result in an invalid C file that can’t be compiled.

Is it possible to temporarily disable synclines for specific lines in m4?