[dev.regabi] all: merge master (fca94ab) into dev.regabi

Conflicts:

- src/syscall/mksyscall.pl

Merge List:

+ 2021-02-02 fca94ab3ab spec: improve the example in Type assertions section
+ 2021-02-02 98f8454a73 cmd/link: don't decode type symbol in shared library in deadcode
+ 2021-02-02 1426a571b7 cmd/link: fix off-by-1 error in findShlibSection
+ 2021-02-01 32e789f4fb test: fix incorrectly laid out instructions in issue11656.go
+ 2021-02-01 0b6cfea634 doc/go1.16: document that on OpenBSD syscalls are now made through libc
+ 2021-02-01 26e29aa15a cmd/link: disable TestPIESize if CGO isn't enabled
+ 2021-02-01 6ac91e460c doc/go1.16: minor markup fixes
+ 2021-01-29 44361140c0 embed: update docs for proposal tweaks
+ 2021-01-29 68058edc39 runtime: document pointer write atomicity for memclrNoHeapPointers
+ 2021-01-28 c8bd8010ff syscall: generate readlen/writelen for openbsd libc
+ 2021-01-28 41bb49b878 cmd/go: revert TestScript/build_trimpath to use ioutil.ReadFile
+ 2021-01-28 725a642c2d runtime: correct syscall10/syscall10X on openbsd/amd64
+ 2021-01-28 4b068cafb5 doc/go1.16: document go/build/constraint package
+ 2021-01-28 376518d77f runtime,syscall: convert syscall on openbsd/arm64 to libc
+ 2021-01-27 00f2ff5c94 api/go1.16: add go/build/constraint APIs
+ 2021-01-27 35334caf18 crypto/x509: remove leftover CertificateRequest field
+ 2021-01-27 a5a5e2c968 runtime: make sure to remove open-coded defer entries in all cases after a recover
+ 2021-01-27 8cfa01943a runtime: block console ctrlhandler when the signal is handled
+ 2021-01-27 ff9e8364c6 cmd/go: skip issue33139 when the 'cc' script command is unavailable
+ 2021-01-27 cd176b3615 runtime: switch runtime to libc for openbsd/arm64
+ 2021-01-27 6c8fbfbdcf runtime: convert openbsd/arm64 locking to libc
+ 2021-01-27 5cdf0da1bf syscall: clean up mkasm related changes
+ 2021-01-27 210f70e298 doc/go1.16: fix closing brace in .Export format
+ 2021-01-27 0f797f168d math: fix typo in sqrt.go code comment
+ 2021-01-26 8634a234df runtime,syscall: convert syscall on openbsd/amd64 to libc
+ 2021-01-26 1d5e14632e os: further document limitations around naked file descriptors
+ 2021-01-26 cf263e9f77 os: correct names in CreateTemp and MkdirTemp doc comments
+ 2021-01-26 ce8b318624 net/http/fcgi: remove locking added to prevent a test-only race

Change-Id: I9e89df040dfbbeb50f4ce653a8da437cb72b3ef9

diff --cc src/embed/embed.go
Simple merge

diff --cc src/syscall/mksyscall.pl
index 26c93ffe5b5ab290995651539f39e3dd69fb457e,67e8d1d99efc02c93488dbea947ebd81c2a498a6..c1ed3a35d97705be137057129000cc13aaadf3ae
--- 1/src/syscall/mksyscall.pl
--- 2/src/syscall/mksyscall.pl
+++ b/src/syscall/mksyscall.pl
@@@ -343,9 -351,16 +351,13 @@@ while(<>) 
                        $trampolines{$funcname} = 1;
                        # The assembly trampoline that jumps to the libc routine.
                        $text .= "func ${funcname}_trampoline()\n";
 -                      # Map syscall.funcname to just plain funcname.
 -                      # (The jump to this function is in the assembly trampoline, generated by mkasm.go.)
 -                      $text .= "//go:linkname $funcname $funcname\n";
                        # Tell the linker that funcname can be found in libSystem using varname without the libc_ prefix.
                        my $basename = substr $funcname, 5;
-                       $text .= "//go:cgo_import_dynamic $funcname $basename \"/usr/lib/libSystem.B.dylib\"\n\n";
+                       my $libc = "libc.so";
+                       if ($darwin) {
+                               $libc = "/usr/lib/libSystem.B.dylib";
+                       }
+                       $text .= "//go:cgo_import_dynamic $funcname $basename \"$libc\"\n\n";
                }
        }
  }