From 813eca64160509465c0e557aa98c9b0f828e47a9 Mon Sep 17 00:00:00 2001 From: Rolf Eike Beer Date: Tue, 3 Jan 2012 19:54:43 +0100 Subject: CheckSymbolExists: force the compiler to keep the referenced symbol Otherwise the compiler may optimize out the reference to the symbol as the previous version was not really using this. This leads to symbols that are only in a header but not in the given libraries to be reported as present. This came up on the first try to fix bug 11333 as "gcc -O3" would optimize out the reference to pthread_create() so the correct library the symbol is in was not detected. The new test code was suggested by Brad King. --- Modules/CheckSymbolExists.cmake | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Modules/CheckSymbolExists.cmake b/Modules/CheckSymbolExists.cmake index 183b2bb..515319d 100644 --- a/Modules/CheckSymbolExists.cmake +++ b/Modules/CheckSymbolExists.cmake @@ -60,7 +60,7 @@ MACRO(_CHECK_SYMBOL_EXISTS SOURCEFILE SYMBOL FILES VARIABLE) "${CMAKE_CONFIGURABLE_FILE_CONTENT}#include <${FILE}>\n") ENDFOREACH(FILE) SET(CMAKE_CONFIGURABLE_FILE_CONTENT - "${CMAKE_CONFIGURABLE_FILE_CONTENT}\nvoid cmakeRequireSymbol(int dummy,...){(void)dummy;}\nint main()\n{\n#ifndef ${SYMBOL}\n cmakeRequireSymbol(0,&${SYMBOL});\n#endif\n return 0;\n}\n") + "${CMAKE_CONFIGURABLE_FILE_CONTENT}\nint main(int argc, char** argv)\n{\n (void)argv;\n#ifndef ${SYMBOL}\n return ((int*)(&${SYMBOL}))[argc];\n#else\n (void)argc;\n return 0;\n#endif\n}\n") CONFIGURE_FILE("${CMAKE_ROOT}/Modules/CMakeConfigurableFile.in" "${SOURCEFILE}" @ONLY IMMEDIATE) -- cgit v0.12