build/seamless-clone: Declare libm dependency
When using poly2tri-c from the subproject, -lm
flag will be inherited
due to some Meson impurity but this is not the case when using poly2tri-c from system:
ld: seamless-clone/libgegl-sc-0.4.so.p/sc-sample.c.o: in function `gegl_sc_compute_sample_list_part':
sc-sample.c:(.text+0x511): undefined reference to `sqrt'
Previously, the distributor could just pass -lm
globally when building GEGL
but since 2348b571, it is no longer possible
because it breaks cc.has_header_symbol()
on Clang:
clang-11: error: -lm: 'linker' input unused [-Werror,-Wunused-command-line-argument]
Let’s declare the dependency explicitly.