1. 22 4月, 2015 13 次提交
    • R
      in visibility preinclude, remove overrides for stdin/stdout/stderr · b8dda24f
      Rich Felker 提交于
      the motivation for this change is that the extra declaration (with or
      without visibility) using "struct _IO_FILE" instead of "FILE" seems to
      trigger a bug in gcc 3.x where it considers the types mismatched.
      however, this change also results in slightly better code and it is
      valid because (1) these three objects are constant, and (2) applying
      the & operator to any of them is invalid C, since they are not even
      specified to be objects. thus it does not matter if the application
      and libc see different addresses for them, as long as the (initial,
      unchanging) value is seen the same by both.
      b8dda24f
    • R
      fix inconsistent visibility for __hwcap and __sysinfo symbols · f203b351
      Rich Felker 提交于
      these are used as hidden by asm files (and such use is the whole
      reason they exist), but their actual definitions were not hidden.
      f203b351
    • R
      remove additional libc struct accessor cruft · 3e827b7e
      Rich Felker 提交于
      commit f9cccfc1 left behind the part
      in libc.c; remove it too.
      3e827b7e
    • R
      remove useless visibility application from static-linking-only code · c267fb84
      Rich Felker 提交于
      part of the goal here is to eliminate use of the ATTR_LIBC_VISIBILITY
      macro outside of libc.h, since it was never intended to be 'public'.
      c267fb84
    • R
      9d836f44
    • R
      remove cruft for libc struct accessor function and broken visibility · f9cccfc1
      Rich Felker 提交于
      these were hacks to work around toolchains that could not properly
      optimize PIC accesses based on visibility and would generate GOT
      lookups even for hidden data, which broke the old dynamic linker.
      since commit f3ddd173 it no longer
      matters; the dynamic linker does not assume accessibility of this data
      until stage 3.
      f9cccfc1
    • R
      make configure check for visibility preinclude compatible with pcc · 428462a4
      Rich Felker 提交于
      pcc does not search for -include relative to the working directory
      unless -I. is used. rather than adding -I., which could be problematic
      if there's extra junk in the top-level directory, switch back to the
      old method (reverting commit 60ed988f)
      of using -include vis.h and relying on -I./src/internal being present
      on the command line (which the Makefile guarantees). to fix the
      breakage that was present in trycppif checks with the old method,
      $CFLAGS_AUTO is removed from the command line passed to trycppif; this
      is valid since $CFLAGS_AUTO should not contain options that alter
      compiler semantics or ABI, only optimizations, warnings, etc.
      428462a4
    • R
      fix duplocale clobbering of new locale struct with memcpy of old · 873e0ec7
      Rich Felker 提交于
      when the non-stub duplocale code was added as part of the locale
      framework in commit 0bc03091, the old
      code to memcpy the old locale object to the new one was left behind.
      the conditional for the memcpy no longer makes sense, because the
      conditions are now always-true when it's reached, and the memcpy is
      wrong because it clobbers the new->messages_name pointer setup just
      above.
      
      since the messages_name and ctype_utf8 members have already been
      copied, all that remains is the cat[] array. these pointers are
      volatile, so using memcpy to copy them is formally wrong; use a for
      loop instead.
      873e0ec7
    • A
      configure: check for -march and -mtune passed via CC · a6274a19
      Andre McCurdy 提交于
      Some build environments pass -march and -mtune as part of CC, therefore
      update configure to check both CC and CFLAGS before making the decision
      to fall back to generic -march and -mtune options for x86.
      Signed-off-by: NAndre McCurdy <armccurdy@gmail.com>
      a6274a19
    • R
      remove dead case for F_SETLKW in fcntl · ea1b6bb6
      Rich Felker 提交于
      the first switch already returns in the F_SETLKW code path so it need
      not be handled in the second switch. moreover the code in the second
      switch is wrong for the F_SETLKW command: it's not cancellable.
      ea1b6bb6
    • R
      fix mmap leak in sem_open failure path for link call · 086793ad
      Rich Felker 提交于
      the leak was found by static analysis (reported by Alexander Monakov),
      not tested/observed, but seems to have occured both when failing due
      to O_EXCL, and in a race condition with O_CREAT but not O_EXCL where a
      semaphore by the same name was created concurrently.
      086793ad
    • R
      remove always-true conditional in dynamic linker TLSDESC processing · c5ab5bd3
      Rich Felker 提交于
      the allocating path which can fail is for dynamic TLS, which can only
      occur at runtime, and the check for runtime was already made in the
      outer conditional.
      c5ab5bd3
    • R
      remove redundant code in do_dlsym function · 97b72d22
      Rich Felker 提交于
      commit 637dd2d3 introduced the checks
      for RTLD_DEFAULT and RTLD_NEXT here, claiming they fixed a regression,
      but the above conditional block clearly already covered these cases,
      and removing the checks produces no difference in the generated code.
      97b72d22
  2. 21 4月, 2015 2 次提交
  3. 20 4月, 2015 5 次提交
    • R
      add optional global visibility override · de2b67f8
      Rich Felker 提交于
      this is implemented via the build system and does not affect source
      files. the idea is to use protected or hidden visibility to prevent
      the compiler from pessimizing function calls within a shared (or
      position-independent static) libc in the form of overhead setting up
      for a call through the PLT. the ld-time symbol binding via the
      -Bsymbolic-functions option already optimized out the PLT itself, but
      not the code in the caller needed to support a call through the PLT.
      on some archs this overhead can be substantial; on others it's
      trivial.
      de2b67f8
    • R
      remove invalid PLT calls from or1k asm · 51fc77c7
      Rich Felker 提交于
      analogous to commit 646cb9a4 for sh.
      51fc77c7
    • R
      remove possible-textrels from powerpc asm · cf1a9d9d
      Rich Felker 提交于
      these are perfectly fine with ld-time symbol binding, but otherwise
      result in textrels. they cannot be replaced with @PLT jump targets
      because the PLT thunks require a GOT register to be setup, so use a
      hidden alias instead.
      cf1a9d9d
    • R
      remove invalid PLT calls from microblaze asm · a880e6ce
      Rich Felker 提交于
      analogous to commit 646cb9a4 for sh.
      a880e6ce
    • R
      remove invalid PLT calls from sh asm · 646cb9a4
      Rich Felker 提交于
      these are perfectly fine with ld-time symbol binding, but if the calls
      go through a PLT thunk, they are invalid because the caller does not
      setup a GOT register. use a hidden alias to bypass the issue.
      646cb9a4
  4. 19 4月, 2015 4 次提交
  5. 18 4月, 2015 15 次提交
    • S
      math: fix pow(+-0,-inf) not to raise divbyzero flag · cb5c057c
      Szabolcs Nagy 提交于
      this reverts the commit f29fea00
      which was based on a bug in C99 and POSIX and did not match IEEE-754
      http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1515.pdf
      cb5c057c
    • R
      apply hidden visibility to tlsdesc accessor functions · 1b1cafa5
      Rich Felker 提交于
      these functions are never called directly; only their addresses are
      used, so PLT indirections should never happen unless a broken
      application tries to redefine them, but it's still best to make them
      hidden.
      1b1cafa5
    • S
      comment fixes in aarch64 tlsdesc asm · ca7977b5
      Szabolcs Nagy 提交于
      ca7977b5
    • R
      ensure debugger hook for dynamic linker does not point to a PLT slot · 326e126f
      Rich Felker 提交于
      this change is made in preparation to support linking without
      -Bsymbolic-functions.
      326e126f
    • S
      add PR_*_FP_MODE prctl options · 02e5d564
      Szabolcs Nagy 提交于
      new in linux v4.0, commit 9791554b45a2acc28247f66a5fd5bbc212a6b8c8
      used to work around a floating-point abi issue on mips
      02e5d564
    • S
      add PR_MPX_*_MANAGEMENT prctl options · 658aefdf
      Szabolcs Nagy 提交于
      new in linux v3.19, commit fe3d197f84319d3bce379a9c0dc17b1f48ad358c
      used for on-demand kernel allocation of bounds tables for mpx on x86
      658aefdf
    • S
      add IP_CHECKSUM socket option to netinet/in.h · 1bfeb1dc
      Szabolcs Nagy 提交于
      new in linux v4.0, commit ad6f939ab193750cc94a265f58e007fb598c97b7
      1bfeb1dc
    • S
      add execveat syscall number to microblaze · 87c62d06
      Szabolcs Nagy 提交于
      syscall number was reserved in linux v4.0, kernel commit
      add4b1b02da7e7ec35c34dd04d351ac53f3f0dd8
      87c62d06
    • R
      improve ctype.h macros to diagnose errors · 2ca55a93
      Rich Felker 提交于
      the casts of the argument to unsigned int suppressed diagnosis of
      errors like passing a pointer instead of a character. putting the
      actual function call in an unreachable branch restores any diagnostics
      that would be present if the macros didn't exist and functions were
      used.
      2ca55a93
    • R
      19bcdeeb
    • R
      fix mips fesetenv(FE_DFL_ENV) again · 8b0d66d2
      Rich Felker 提交于
      commit 5fc14878 attempted to fix it,
      but neglected the fact that mips has branch delay slots.
      8b0d66d2
    • R
      fix PLT call offset in sh dlsym asm · aecdbb30
      Rich Felker 提交于
      the braf instruction's destination register is an offset from the
      address of the braf instruction plus 4 (or equivalently, the address
      of the next instruction after the delay slot). the code for dlsym was
      incorrectly computing the offset to pass using the address of the
      delay slot itself. in other places, a label was placed after the delay
      slot, but I find this confusing. putting the label on the branch
      instruction itself, and manually adding 4, makes it more clear which
      branch the offset in the constant pool goes with.
      aecdbb30
    • R
      fix sh build regressions in asm · 33615cd5
      Rich Felker 提交于
      even hidden functions need @PLT symbol references; otherwise an
      absolute address is produced instead of a PC-relative one.
      33615cd5
    • R
      fix sh __set_thread_area uninitialized return value · 64fbd15f
      Rich Felker 提交于
      this caused the dynamic linker/startup code to abort when r0 happened
      to contain a negative value.
      64fbd15f
    • R
      redesign sigsetjmp so that signal mask is restored after longjmp · 583e5512
      Rich Felker 提交于
      the conventional way to implement sigsetjmp is to save the signal mask
      then tail-call to setjmp; siglongjmp then restores the signal mask and
      calls longjmp. the problem with this approach is that a signal already
      pending, or arriving between unmasking of signals and restoration of
      the saved stack pointer, will have its signal handler run on the stack
      that was active before siglongjmp was called. this can lead to
      unbounded stack usage when siglongjmp is used to leave a signal
      handler.
      
      in the new design, sigsetjmp saves its own return address inside the
      extended part of the sigjmp_buf (outside the __jmp_buf part used by
      setjmp) then calls setjmp to save a jmp_buf inside its own execution.
      it then tail-calls to __sigsetjmp_tail, which uses the return value of
      setjmp to determine whether to save the current signal mask or restore
      a previously-saved mask.
      
      as an added bonus, this design makes it so that siglongjmp and longjmp
      are identical. this is useful because the __longjmp_chk function we
      need to add for ABI-compatibility assumes siglongjmp and longjmp are
      the same, but for different reasons -- it was designed assuming either
      can access a flag just past the __jmp_buf indicating whether the
      signal masked was saved, and act on that flag. however, early versions
      of musl did not have space past the __jmp_buf for the non-sigjmp_buf
      version of jmp_buf, so our setjmp cannot store such a flag without
      risking clobbering memory on (very) old binaries.
      583e5512
  6. 15 4月, 2015 1 次提交
    • R
      use hidden __tls_get_new for tls/tlsdesc lookup fallback cases · 81e18eb3
      Rich Felker 提交于
      previously, the dynamic tlsdesc lookup functions and the i386
      special-ABI ___tls_get_addr (3 underscores) function called
      __tls_get_addr when the slot they wanted was not already setup;
      __tls_get_addr would then in turn also see that it's not setup and
      call __tls_get_new.
      
      calling __tls_get_new directly is both more efficient and avoids the
      issue of calling a non-hidden (public API/ABI) function from asm.
      
      for the special i386 function, a weak reference to __tls_get_new is
      used since this function is not defined when static linking (the code
      path that needs it is unreachable in static-linked programs).
      81e18eb3