# Software notes

This document lists some software known to build successfully, and any
special procedures necessary.

## sbase

Builds without issue.

## mcpp

Builds without issue. Requires `CFLAGS=-D_POSIX_C_SOURCE=200112L`.

## binutils

On musl systems, you must define `long double` to match `double` (as
below) to avoid errors in unused `static inline` functions in musl's
`math.h`. Note: this is a hack and won't be ABI-incompatible with musl;
things will break if any functions with `long double` get called.

```diff
-struct type typeldouble = FLTTYPE(TYPELDOUBLE, 16, NULL);  // XXX: not supported by qbe
+struct type typeldouble = FLTTYPE(TYPELDOUBLE, 8, &f64);
```

Requires several patches available here:
https://github.com/michaelforney/binutils-gdb/tree/cc-fixes

- Fix function pointer subtraction in `bfd/doc/chew.c` (applied upstream).
- Skip unsupported `LDFLAGS`, only tested to work against `CXX` by
  configure, but applied to `CC` as well.
- Disable `long double` support in `_bfd_doprnt`.
- Alter some ifdefs to avoid statement expressions and VLAs.
- Implement `pex_unix_exec_child` with `posix_spawn` instead of `vfork`
  and subtle `volatile` usage.
- Make `regcomp` and `regexec` match the header declaration in usage of
  `restrict`.
- Don't declare `vasprintf` unless it was checked for and not
  found (applied to libiberty upstream).
- Make sure `config.h` is included in `arlex.c` so that the appropriate
  feature-test macros get defined to expose `strdup`.

Configure with

```
./configure CFLAGS_FOR_BUILD=-D_GNU_SOURCE \
	--disable-intl --disable-gdb --disable-plugins --disable-readline
```

[f6a7d135]: https://git.sr.ht/~mcf/qbe/commit/f6a7d135d54f5281547f20cc4f72a5e85862157c

## gcc 4.7

Requires a number patches available here:
https://github.com/michaelforney/gcc/tree/cc-fixes

Also requires gmp headers modified for C99 inline semantics:
https://hg.sr.ht/~mcf/gmp-6.1/rev/53195faa26dfeafeacd57f54035373988e2a16a3

Build with

```
git clone -b cc-fixes https://github.com/michaelforney/gcc
cd gcc
hg clone https://hg.sr.ht/~mcf/gmp-6.1 gmp
(cd gmp && aux_dir=. ltdl_dir=. ./.bootstrap)
./configure --disable-multilib --disable-bootstrap --disable-lto --enable-languages=c,c++
make
```

## zstd

Requires disabling CPU identification inline assembly and deprecation
warnings.

```diff
diff --git a/lib/common/cpu.h b/lib/common/cpu.h
index 5f0923fc..10dd7d7f 100644
--- a/lib/common/cpu.h
+++ b/lib/common/cpu.h
@@ -52,6 +52,7 @@ MEM_STATIC ZSTD_cpuid_t ZSTD_cpuid(void) {
             f7c = (U32)reg[2];
         }
     }
+#elif 1
 #elif defined(__i386__) && defined(__PIC__) && !defined(__clang__) && defined(__GNUC__)
     /* The following block like the normal cpuid branch below, but gcc
      * reserves ebx for use of its pic register so we must specially
```

Build with

	make CC=/path/to/cc CFLAGS='-DZDICT_DISABLE_DEPRECATE_WARNINGS -DZBUFF_DISABLE_DEPRECATE_WARNINGS' zstd

## st

Requires a few changes to avoid wide string literals and including
`math.h` on musl targets.

```diff
diff --git a/config.def.h b/config.def.h
index 482901e..bd963ae 100644
--- a/config.def.h
+++ b/config.def.h
@@ -32,7 +32,7 @@ static float chscale = 1.0;
  *
  * More advanced example: L" `'\"()[]{}"
  */
-wchar_t *worddelimiters = L" ";
+wchar_t *worddelimiters = (wchar_t[]){' ', 0};
 
 /* selection timeouts (in milliseconds) */
 static unsigned int doubleclicktimeout = 300;
diff --git a/x.c b/x.c
index 5828a3b..6e006cc 100644
--- a/x.c
+++ b/x.c
@@ -1,6 +1,5 @@
 /* See LICENSE for license details. */
 #include <errno.h>
-#include <math.h>
 #include <limits.h>
 #include <locale.h>
 #include <signal.h>
@@ -15,6 +14,8 @@
 #include <X11/Xft/Xft.h>
 #include <X11/XKBlib.h>
 
+float ceilf(float);
+
 static char *argv0;
 #include "arg.h"
 #include "st.h"
```