Compile fixes for building with musl libc #201
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The timer_t type is not used anywhere in the code. The fallback typedef can break builds though on systems where timer_t exists but is not an alias for __timer_t, such as systems using the musl libc. Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
There is no guarantee that <sys/param.h> defines HZ. And in musl libc, it doesn't. Since this is a Linux-specific constant, include the Linux-specific header for it. Note that HZ as defined by the system headers is the default value of HZ (100), which might differ from the actual value of HZ in the kernel config. Ideally userland would not use HZ at all and do all timing in milliseconds instead. Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
This looks like a sanity check that 64-bit file offset definitions were indeed provided by the included headers. But __USE_FILE_OFFSET64 is an internal define of glibc, so don't perform this check when compiling with a different libc. Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
The type of "st_mode" in "struct stat" is "mode_t", not "__mode_t". Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
Previously, "-D__STDC_VERSION__=199901L" was used to request C99 functionality from the system headers, but this does not tell the compiler to provide C99 language features, so for example the "restrict" keyword is not available then. This mismatch breaks the build when using musl libc. Instead we use "-std=c99" to select C99, but this has the side effect of disabling non-standard APIs. So we have to manually re-select those. The simplest way of doing so is "-D_DEFAULT_SOURCE", but that is not universally supported yet by libcs, so for now I opted for the more portable "-D_POSIX_C_SOURCE=199309L" to get access to clock_gettime() and maybe other functionality not in the C99 standard. Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
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Today I rebased on the current master and added one commit to fix new compile errors (the C99 one). It now builds fine with musl 1.1.5. |
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Compile fixes for building with musl libc
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The musl libc library is an embedded libc that is gaining popularity. The following cleanups fix compile errors where musl does things differently from glibc, but within the specs. They should be safer on all platforms.