From 81f6dd86b785dc78d80bf1291295c1b51d919d37 Mon Sep 17 00:00:00 2001 From: "Wladimir J. van der Laan" Date: Mon, 14 Dec 2020 21:00:49 +0100 Subject: [PATCH] Merge #20594: Fix getauxval calls in randomenv.cpp 836a3dc02c72f917db5be386b9b4787a59d48610 Avoid weak-linked getauxval support on non-linux platforms (like macOS) (Jonas Schnelli) 41a413b31746cc749f3c64ed8070cea9cc6cfdbe Define correct symbols for getauxval (Jonas Schnelli) Pull request description: PR #20358 made use of the two preprocessor symbols `HAVE_STRONG_GETAUXVAL` as well as `HAVE_WEAK_GETAUXVAL`. These symbols have not been defined in configure.ac. They where only passed selective as CRC32 CPPFLAGS in https://github.com/bitcoin/bitcoin/blob/master/src/Makefile.crc32c.include#L16. PR #20358 would have broken the macOS build since `getauxval` is not supported on macOS (but weak-linking does pass). This PR defines the two symbols correctly and reduces calls to `getauxval` to linux. ACKs for top commit: laanwj: Code review ACK 836a3dc02c72f917db5be386b9b4787a59d48610 jonatack: utACK 836a3dc02c72f917db5be386b9b4787a59d48610 Tree-SHA512: 6527f4a617b937f4c368a3cb1c162f1ac38a6f5e6341295554961eaf322906e9b27398a6f7b00819854ceebb5c828d3e6ce0a779edd769adc4053ce8beda3739 --- configure.ac | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/configure.ac b/configure.ac index dbb8d03f5e..b3b2c3cd93 100644 --- a/configure.ac +++ b/configure.ac @@ -1050,18 +1050,20 @@ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[ ]], [[ getauxval(AT_HWCAP); ]])], - [ AC_MSG_RESULT(yes); HAVE_STRONG_GETAUXVAL=1 ], + [ AC_MSG_RESULT(yes); HAVE_STRONG_GETAUXVAL=1; AC_DEFINE(HAVE_STRONG_GETAUXVAL, 1, [Define this symbol to build code that uses getauxval)]) ], [ AC_MSG_RESULT(no); HAVE_STRONG_GETAUXVAL=0 ] ) AC_MSG_CHECKING(for weak getauxval support in the compiler) AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[ + #ifdef __linux__ unsigned long getauxval(unsigned long type) __attribute__((weak)); #define AT_HWCAP 16 + #endif ]], [[ getauxval(AT_HWCAP); ]])], - [ AC_MSG_RESULT(yes); HAVE_WEAK_GETAUXVAL=1 ], + [ AC_MSG_RESULT(yes); HAVE_WEAK_GETAUXVAL=1; AC_DEFINE(HAVE_WEAK_GETAUXVAL, 1, [Define this symbol to build code that uses getauxval (weak linking)]) ], [ AC_MSG_RESULT(no); HAVE_WEAK_GETAUXVAL=0 ] )