As for LD_SHOW_AUXV=yes, I tried different combinations and it is always ignored, no matter what.
Thanks for investigating. It might be related to elf notes supplied by kernel.
FreeBSD 9 added these defines:
#define AT_CANARY 16 /* Canary for SSP. */
#define AT_CANARYLEN 17 /* Length of the canary. */
#define AT_OSRELDATE 18 /* OSRELDATE. */
#define AT_NCPUS 19 /* Number of CPUs. */
#define AT_PAGESIZES 20 /* Pagesizes. */
#define AT_PAGESIZESLEN 21 /* Number of pagesizes. */
#define AT_STACKPROT 23 /* Initial stack protection. */
And under Linux:
#define AT_HWCAP 16 /* Machine dependent hints about
#define AT_CLKTCK 17 /* Frequency of times() */
processor capabilities. */
/* This entry gives some information about the FPU initialization
performed by the kernel. */
#define AT_FPUCW 18 /* Used FPU control word. */
/* Cache block sizes. */
#define AT_DCACHEBSIZE 19 /* Data cache block size. */
#define AT_ICACHEBSIZE 20 /* Instruction cache block size. */
#define AT_UCACHEBSIZE 21 /* Unified cache block size. */
/* A special ignored value for PPC, used by the kernel to control the
interpretation of the AUXV. Must be > 16. */
#define AT_IGNOREPPC 22 /* Entry should be ignored. */
#define AT_SECURE 23 /* Boolean, was exec setuid-like? */
#define AT_BASE_PLATFORM 24 /* String identifying real platforms.*/
#define AT_RANDOM 25 /* Address of 16 random bytes. */
#define AT_EXECFN 31 /* Filename of executable. */
It looks like a collision, namely between
AT_STACKPROT x AT_SECURE
Petr