lib/glibc
1
0
Fork 0
mirror of https://sourceware.org/git/glibc.git synced 2025-08-01 10:06:57 +03:00
Code Activity

soft-fp: Support conditional zero-initialization in declarations.

Browse Source 
In the Linux kernel, some architectures have a single function that
uses different kinds of unpacking and packing depending on the
instruction being emulated, meaning it is not readily visible to the
compiler that variables from _FP_DECL and _FP_FRAC_DECL_* macros are
only used in cases where they were initialized.  The existing copy of
soft-fp in the Linux kernel uses zero-initialization to avoid warnings
in this case, so while frowned upon as a warning suppression mechanism
in code built for glibc it seems appropriate to have such
zero-initialization conditional on __KERNEL__.  This patch duly adds
it, via a macro _FP_ZERO_INIT that expands to empty for non-kernel
compilations.

Tested for powerpc-nofpu that installed stripped shared libraries are
unchanged by this patch.

	* soft-fp/soft-fp.h (_FP_ZERO_INIT): New macro.  Define depending
	on [__KERNEL__].
	* soft-fp/op-1.h (_FP_FRAC_DECL_1): Use _FP_ZERO_INIT.
	* soft-fp/op-2.h (_FP_FRAC_DECL_2): Likewise.
	* soft-fp/op-common.h (_FP_DECL): Likewise.
This commit is contained in:
Joseph Myers
2015-03-07 01:39:42 +00:00
parent e0ed2fb40a
commit b838844bc5
5 changed files with 26 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
soft-fp/soft-fp.h
View File

@ -51,6 +51,17 @@
# endif
#endif
/* In the Linux kernel, some architectures have a single function that
uses different kinds of unpacking and packing depending on the
instruction being emulated, meaning it is not readily visible to
the compiler that variables from _FP_DECL and _FP_FRAC_DECL_*
macros are only used in cases where they were initialized. */
#ifdef __KERNEL__
# define _FP_ZERO_INIT = 0
#else
# define _FP_ZERO_INIT
#endif
#define _FP_WORKBITS 3
#define _FP_WORK_LSB ((_FP_W_TYPE) 1 << 3)
#define _FP_WORK_ROUND ((_FP_W_TYPE) 1 << 2)