panic: template: MakeCmd:35: unexpected bad character U+003D '=' in if

[fw42]

When trying to run gb on Darwin, I get this:

$ go get code.google.com/p/go-gb/gb
$ gb
panic: template: MakeCmd:35: unexpected bad character U+003D '=' in if

goroutine 1 [running]:
text/template.Must(0x0, 0x22083817c0, 0x20837c470, 0x0)
    /usr/local/Cellar/go/1.4.2/libexec/src/text/template/helper.go:23 +0x50
main.init()
    /Users/flo/go/src/code.google.com/p/go-gb/gb/genmake.go:74 +0x647
$ uname -a
Darwin flombp 13.4.0 Darwin Kernel Version 13.4.0: Wed Mar 18 16:20:14 PDT 2015; root:xnu-2422.115.14~1/RELEASE_X86_64 x86_64 i386 MacBookPro10,2 Darwin
$ go version
go version go1.4.2 darwin/amd64

Any idea?