commit 6f7ec059bc (Remove dead stores) breaks -DSTACKCHECK

[nbriggs]

clang -m32 -std=gnu99 -fno-strict-aliasing -fwrapv -c -O2 -g  -DMACOSX -DOLD_CURSOR -DBYTESWAP -DLOGINT  -I/opt/X11/include -DXWINDOW -DNOPIXRECT -DRELEASE=351 -DSTACKCHECK -DFSBCHECK -DPCTRACE  -I../inc/ -I../include/ ../src/llstk.c  -o ../darwin.386-x/llstk.o
../src/llstk.c:340:7: error: expected expression
      StackWord *orig68k = scanptr68k;
      ^
../src/llstk.c:349:27: error: use of undeclared identifier 'orig68k'
        if (scanptr68k != orig68k) {
                          ^
../src/llstk.c:354:64: error: use of undeclared identifier 'orig68k'
        if (((Bframe *)scanptr68k)->ivar != StkOffset_from_68K(orig68k)) {
                                                               ^
3 errors generated.
make: *** [../darwin.386-x/llstk.o] Error 1

[nbriggs]

It leaves a declaration in the middle of code, not at the start of a { } block. Wrapping the code as default: { code } is a potential fix for this.