filter -ffast-math and add USE flags

[stefan11111]

Closes: #129

See:
https://developer.palemoon.org/build/linux/
https://forum.palemoon.org/viewtopic.php?f=5&t=30227
https://repo.palemoon.org/MoonchildProductions/Pale-Moon/issues/1934
https://repo.palemoon.org/MoonchildProductions/Pale-Moon/issues/1932

Adds USE flags to, among other things, make possible to create a .mozconfig simmilar to the default one and to not build things like drm and webrtc, the latter doesn't work with palemoon in any configuration.

Also added filtering for the -ffast-math CFLAG, because it results in runtime failures.

There is currently a build issue with binutils 2.41.
The way to fix that is to add this commit as a patch:
https://git.ffmpeg.org/gitweb/ffmpeg.git/commit/effadce6c756247ea8bae32dc13bb3e6f464f0eb

I didn't do that here because it's easy enough to do that locally and it will likely be fixed upstream soon enough. You can add it if you want:

--- a/platform/media/ffvpx/libavcodec/x86/mathops.h
+++ b/platform/media/ffvpx/libavcodec/x86/mathops.h
@@ -35,12 +35,20 @@
 static av_always_inline av_const int MULL(int a, int b, unsigned shift)
 {
     int rt, dummy;
+    if (__builtin_constant_p(shift))
     __asm__ (
         "imull %3               \n\t"
         "shrdl %4, %%edx, %%eax \n\t"
         :"=a"(rt), "=d"(dummy)
-        :"a"(a), "rm"(b), "ci"((uint8_t)shift)
+        :"a"(a), "rm"(b), "i"(shift & 0x1F)
     );
+    else
+        __asm__ (
+            "imull %3               \n\t"
+            "shrdl %4, %%edx, %%eax \n\t"
+            :"=a"(rt), "=d"(dummy)
+            :"a"(a), "rm"(b), "c"((uint8_t)shift)
+        );
     return rt;
 }

@@ -113,19 +121,31 @@ __asm__ volatile(\
 // avoid +32 for shift optimization (gcc should do that ...)
 #define NEG_SSR32 NEG_SSR32
 static inline  int32_t NEG_SSR32( int32_t a, int8_t s){
+    if (__builtin_constant_p(s))
     __asm__ ("sarl %1, %0\n\t"
          : "+r" (a)
-         : "ic" ((uint8_t)(-s))
+         : "i" (-s & 0x1F)
     );
+    else
+        __asm__ ("sarl %1, %0\n\t"
+               : "+r" (a)
+               : "c" ((uint8_t)(-s))
+        );
     return a;
 }

 #define NEG_USR32 NEG_USR32
 static inline uint32_t NEG_USR32(uint32_t a, int8_t s){
+    if (__builtin_constant_p(s))
     __asm__ ("shrl %1, %0\n\t"
          : "+r" (a)
-         : "ic" ((uint8_t)(-s))
+         : "i" (-s & 0x1F)
     );
+    else
+        __asm__ ("shrl %1, %0\n\t"
+               : "+r" (a)
+               : "c" ((uint8_t)(-s))
+        );
     return a;
 }

There is also the following patch which from my shallow testing may or may not slightly decrease build time. I didn't include it.

--- a/platform/python/mozbuild/mozbuild/test/configure/test_moz_configure.py    2023-08-29 21:25:40.505674044 +0300
+++ b/platform/python/mozbuild/mozbuild/test/configure/test_moz_configure.py    2023-08-29 21:27:34.903987259 +0300
@@ -31,13 +31,6 @@
                           get_value_for(['--enable-application=browser',
                                          'MOZ_PROFILING=1']))

-        value = get_value_for(
-            environ={'MOZ_PROFILING': '1'},
-            mozconfig='ac_add_options --enable-project=js')
-
-        self.assertEquals('--enable-project=js MOZ_PROFILING=1',
-                          value)
-
         # --disable-js-shell is the default, so it's filtered out.
         self.assertEquals('--enable-application=browser',
                           get_value_for(['--enable-application=browser',
--- a/platform/js/src/configure.in      2023-08-29 21:25:27.409200482 +0300
+++ b/platform/js/src/configure.in      2023-08-29 21:26:33.831554428 +0300
@@ -22,6 +22,6 @@
 TOPSRCDIR="$SRCDIR"/../..
 export OLD_CONFIGURE="$SRCDIR"/old-configure

-set -- "$@" --enable-project=js
+set -- "$@"

 which python2.7 > /dev/null && exec python2.7 "$TOPSRCDIR/configure.py" "$@" || exec python "$TOPSRCDIR/configure.py" "$@"
--- a/platform/build/subconfigure.py    2023-08-29 21:24:50.939738219 +0300
+++ b/platform/build/subconfigure.py    2023-08-29 21:26:11.801879253 +0300
@@ -317,7 +317,6 @@
             command = [
                 sys.executable,
                 os.path.join(os.path.dirname(__file__), '..', 'configure.py'),
-                '--enable-project=js',
             ]
             data['env']['OLD_CONFIGURE'] = os.path.join(
                 os.path.dirname(configure), 'old-configure')

[l29ah]

What is the strip USE for? portage already handles stripping via a separate setting, and packages are encouraged not to strip by themselves: https://wiki.gentoo.org/wiki/Debugging

[stefan11111]

I don't get what you mean.
I see no strip in IUSE. You mean FETURES="strip"? I don't see the relevance.
Also, I didn't say anything about stripping symbols, which is what that link is about.

[l29ah]

I see no strip in IUSE.

https://github.com/deu/palemoon-overlay/pull/138/files#diff-3fbbd815e61021b96a355a58ce1c2e5b89aa59731ca1b5162c93bddb03e9ec06R32

[stefan11111]

Ah... sorry.

What about the rest?

[l29ah]

profiles/package.use.mask change is puzzling, otherwise LGTM, assuming you have verified that the new USE flags work.

[stefan11111]

The new USE flags do seem to work, but I'd have to do 128(2^7) builds to test all configurations.
The profiles/package.use.mask changes are there because of upstream bugs.
./mach mozpackage doesn't work properly with system-hunspell.
The build fails with system-cairo.
I can't do anything about these other that to mask the USE flags.

[stefan11111]

So... anything else to say.
I do have maintainer edits turned on.

[l29ah]

@deu can you please take a look at this? I don't feel comfortable accepting such an involved patch singlehandedly.

[freetolga]

palemoon absolutely recommends against system libraries