Comparison with "true" in source code

There are some "== true" in the codes, but they might not be safe
because all non-zero values are true in C. Is it worth cleaning up them?

src/backend/access/gin/ginget.c(1364):#define GinIsVoidRes(s)        (
((GinScanOpaque) scan->opaque)->isVoidRes == true )
src/backend/access/gist/gistproc.c(383):        if (allisequal == true && (
src/backend/commands/sequence.c(1107):        Assert(new->is_cycled == false
|| new->is_cycled == true);
src/backend/tsearch/regis.c(251):                if (mb_strchr((char *) ptr->data,
c) == true)
src/backend/utils/adt/geo_ops.c(3899):    for (i = start; i < poly->npts
&& res == true; i++)
src/backend/utils/adt/geo_ops.c(3975):        for (i = 0; i < polyb->npts &&
result == true; i++)
src/backend/utils/adt/tsrank.c(112):    if (item->prefix == true)
src/backend/utils/adt/tsvector_op.c(628):    if (res == false &&
val->prefix == true)
src/include/c.h(475):#define BoolIsValid(boolean)    ((boolean) == false
|| (boolean) == true)
src/bin/psql/print.c(832):                    if (opt_border != 0 ||
format->wrap_right_border == true)
src/interfaces/ecpg/ecpglib/connect.c(168):    if (con->autocommit ==
true && strncmp(mode, "off", strlen("off")) == 0)
src/interfaces/ecpg/preproc/ecpg.addons(356):        if (compat ==
ECPG_COMPAT_INFORMIX_SE && autocommit == true)
src/interfaces/ecpg/preproc/ecpg.c(310):                    ptr2ext[3] = (header_mode
== true) ? 'h' : 'c';
src/interfaces/ecpg/preproc/ecpg.c(327):                    ptr2ext[1] = (header_mode
== true) ? 'h' : 'c';

-- 
Itagaki Takahiro