diff options
| author | H.J. Lu <hjl.tools@gmail.com> | 2018-02-23 11:29:27 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2018-02-23 11:29:39 -0800 |
| commit | f5d1f629c693bc30ccc8ff1246cb37986c1adb1c (patch) | |
| tree | 7ab5aa175267326f4e8aeeb600034a52e3aaafbb /Makerules | |
| parent | 54412d20618b7b93f136a168e788573575f8a7a6 (diff) | |
| download | glibc-f5d1f629c693bc30ccc8ff1246cb37986c1adb1c.tar.gz glibc-f5d1f629c693bc30ccc8ff1246cb37986c1adb1c.tar.xz glibc-f5d1f629c693bc30ccc8ff1246cb37986c1adb1c.zip | |
Define GEN_AS_CONST_HEADERS when generating header files [BZ #22792]
Glibc build generates header files to define constants from special .sym files. If a .sym file includes the same header file which it generates, it leads to circular dependency which may lead to build hang on a many-core machine. Define GEN_AS_CONST_HEADERS when generating header files to avoid circular dependency. <tcb-offsets.h> is needed for i686 and it isn't needed for x86-64 at least since glibc 2.23. Tested on i686 and x86-64. [BZ #22792] * Makerules ($(common-objpfx)%.h): Pass -DGEN_AS_CONST_HEADERS to $(CC). * sysdeps/unix/sysv/linux/i386/lowlevellock.h: Include <tcb-offsets.h> only if GEN_AS_CONST_HEADERS isn't defined. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.h: Don't include <tcb-offsets.h>.
Diffstat (limited to 'Makerules')
| -rw-r--r-- | Makerules | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/Makerules b/Makerules index ef6abeac6d..b2c2724fcb 100644 --- a/Makerules +++ b/Makerules @@ -276,10 +276,17 @@ ifdef gen-as-const-headers # Generating headers for assembly constants. # We need this defined early to get into before-compile before # it's used in sysd-rules, below. +# Define GEN_AS_CONST_HEADERS to avoid circular dependency [BZ #22792]. +# NB: <tcb-offsets.h> is generated from tcb-offsets.sym to define +# offsets and sizes of types in <tls.h> and maybe <pthread.h> which +# may include <tcb-offsets.h>. Target header files can check if +# GEN_AS_CONST_HEADERS is defined to avoid circular dependency which +# may lead to build hang on a many-core machine. $(common-objpfx)%.h $(common-objpfx)%.h.d: $(..)scripts/gen-as-const.awk \ %.sym $(common-before-compile) $(AWK) -f $< $(filter %.sym,$^) \ - | $(CC) -S -o $(@:.h.d=.h)T3 $(CFLAGS) $(CPPFLAGS) -x c - \ + | $(CC) -S -o $(@:.h.d=.h)T3 $(CFLAGS) $(CPPFLAGS) \ + -DGEN_AS_CONST_HEADERS -x c - \ -MD -MP -MF $(@:.h=.h.d)T -MT '$(@:.h=.h.d) $(@:.h.d=.h)' sed -n 's/^.*@@@name@@@\([^@]*\)@@@value@@@[^0-9Xxa-fA-F-]*\([0-9Xxa-fA-F-][0-9Xxa-fA-F-]*\).*@@@end@@@.*$$/#define \1 \2/p' \ $(@:.h.d=.h)T3 > $(@:.h.d=.h)T |