create distinct interned string type

Interned strings are used pervasively, so it's a good idea to add a
layer of type safety to differentiate them from general cstrs and avoid
potential bugs from comparing non-interned and interned strings. Not
that that's happened so far that I can remember, but it could.

I'm 90% sure it's legal to alias `struct {char c;}` pointers with `char`
pointers. This specific typedef gives type safety but with a simple
one-way `internstr -> const char *` typecast (with `&istr->c`).
Converting the other way around is more intentional: a straight up cast
`(internstr)cstr` which sticks out as unchecked and probably wrong, or
calling the intern(cstr) function, which is the right way.

1 files changed, 4 insertions, 4 deletions

diff --git a/obj/obj.h b/obj/obj.h
index 59769ff..77da99a 100644
--- a/obj/obj.h
+++ b/obj/obj.h
@@ -22,10 +22,10 @@ enum relockind {
 enum section { Snone, Stext, Srodata, Sdata, Sbss };
 
 void objini(const char *infile, const char *outfile);
-void objdeffunc(const char *nam, bool globl, uint off, uint siz);
-enum section objhassym(const char *name, uint *off);
-uint objnewdat(const char *name, enum section, bool globl, uint siz, uint align);
-void objreloc(const char *sym, enum relockind, enum section, uint off, vlong addend);
+void objdeffunc(internstr nam, bool globl, uint off, uint siz);
+enum section objhassym(internstr name, uint *off);
+uint objnewdat(internstr name, enum section, bool globl, uint siz, uint align);
+void objreloc(internstr sym, enum relockind, enum section, uint off, vlong addend);
 void objfini(void);
 
 /* vim:set ts=3 sw=3 expandtab: */