Skip to content

outcoff.c: Function type extension to the global, extern & static directives #233

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
bird2tori wants to merge 2 commits into from
Closed

outcoff.c: Function type extension to the global, extern & static directives #233

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
6daa583
outcoff.c: Added support for 'function' type on global symbols.
May 10, 2026
1642ce6
doc/outfmt.src: Documented 'function' win32/64 symbol type.
May 12, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
14 changes: 14 additions & 0 deletions doc/outfmt.src
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -759,6 +759,20 @@ data for "safe exception handler table" causes no backward
incompatibilities and "safeseh" modules generated by NASM 2.03 and
later can still be linked by earlier versions or non-Microsoft linkers.

\S{win32glob} \c{win32} Extensions to the \c{GLOBAL}, \c{EXTERN} and \c{STATIC} Directives\I{GLOBAL,
win32 extensions to}\I{EXTERN, win32 extensions to}\I{STATIC, win32 extensions to}

You can specify whether a symbol is a function by suffixing the name
with a colon and the word \i\c{function}. For example:

\c global hashlookup:function
\c static localfunc:function
\c extern extfunc:function

The linker may use this extra symbol information when generating tables of
valid indirect branch targets and such.


\S{codeview} Debugging formats for Windows
\I{Windows debugging formats}

Expand Down
22 changes: 19 additions & 3 deletions output/outcoff.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -539,16 +539,18 @@ static void coff_deflabel(char *name, int32_t segment, int64_t offset,
int pos, section;
struct coff_Symbol *sym;

if (special)
nasm_nonfatal("COFF format does not support any"
" special symbol types");
nasm_debug(2, " coff_deflabel: %s, seg=%"PRIx32", off=%"PRIx64", is_global=%d, %s, coff_nsyms=%"PRIu32"\n",
name, segment, offset, is_global, special, coff_nsyms);

if (name[0] == '.' && name[1] == '.' && name[2] != '@') {
if (strcmp(name,WRT_IMAGEBASE))
nasm_nonfatal("unrecognized special symbol `%s'", name);
return;
}

if (is_global == 3) /* discard special-retry from pass two. */
return;

if (segment == NO_SEG)
section = -1; /* absolute symbol */
else {
Expand Down Expand Up @@ -598,6 +600,20 @@ static void coff_deflabel(char *name, int32_t segment, int64_t offset,
else
sym->value = (sym->section == 0 ? 0 : offset);

if (special) {
special = nasm_skip_spaces(special);
while (*special) {
const char *wend = nasm_skip_word(special);
size_t wlen = wend - special;
if (wlen == 8 && !nasm_strnicmp(special, "function", 8))
sym->type = 0x20; /* DT_FCN */
else
nasm_nonfatal("unrecognised symbol type `%*.*s' on `%s'",
(int)wlen, (int)wlen, special, name);
special = nasm_skip_spaces(wend);
}
}

/*
* define the references from external-symbol segment numbers
* to these symbol records.
Expand Down