Generate stubs that tell you when they are called. Helpful when componentizing for test.

gccmock.rb

# gccmock - generate exploding link stubs from linker error messages
#
# Usage: gcc [files] 2>&1 ruby gccmock.rb > [filename].c

LINK_SYMBOL = /.*"_([_a-z0-9]*)",/

puts "#include <assert.h>\n"
puts "#define EXPLODE(name) void name() { assert(!\"unexpected call\"); }"
puts ARGF.select { |line| LINK_SYMBOL =~ line }      \
         .map { |line| LINK_SYMBOL.match(line)[1] }  \
         .uniq                                       \
         .sort                                       \
         .map { |name| "EXPLODE(#{name});" }         \
         .join($/)