| From ea50be0529c248961e1b66293f8a9e4b807294a6 Mon Sep 17 00:00:00 2001 |
| From: Samuel Martin <s.martin49@gmail.com> |
| Date: Sun, 12 Oct 2014 10:17:23 +0200 |
| Subject: [PATCH] core: fix x86 PIC code compilation |
| |
| This bug was triggered by Buildroot autobuilders [1,2], causing this |
| kind of failures [3,4]: |
| |
| [ 14%] Building CXX object modules/core/CMakeFiles/opencv_core.dir/src/system.cpp.o |
| /home/test/autobuild/instance-0/output/build/opencv-2.4.10/modules/core/src/system.cpp: In function '(static initializers for /home/test/autobuild/instance-0/output/build/opencv-2.4.10/modules/core/src/system.cpp)': |
| /home/test/autobuild/instance-0/output/build/opencv-2.4.10/modules/core/src/system.cpp:280:10: error: inconsistent operand constraints in an 'asm' |
| make[3]: *** [modules/core/CMakeFiles/opencv_core.dir/src/system.cpp.o] Error 1 |
| |
| [1] http://buildroot.org/ |
| [2] http://autobuild.buildroot.org/ |
| [3] http://autobuild.buildroot.org/?reason=opencv-2.4.10 |
| [4] http://autobuild.buildroot.org/results/483/4838285b25d6293a5cf0bb9eadd5040a7c75d766/build-end.log |
| |
| Signed-off-by: Samuel Martin <s.martin49@gmail.com> |
| --- |
| modules/core/src/system.cpp | 5 ++++- |
| 1 file changed, 4 insertions(+), 1 deletion(-) |
| |
| diff --git a/modules/core/src/system.cpp b/modules/core/src/system.cpp |
| index 5a970d5..e9ffdc7 100644 |
| --- a/modules/core/src/system.cpp |
| +++ b/modules/core/src/system.cpp |
| @@ -267,14 +267,17 @@ struct HWFeatures |
| : "cc" |
| ); |
| #else |
| + // We need to preserve ebx since we are compiling PIC code. |
| + // This means we cannot use "=b" for the 2nd output register. |
| asm volatile |
| ( |
| "pushl %%ebx\n\t" |
| "movl $7,%%eax\n\t" |
| "movl $0,%%ecx\n\t" |
| "cpuid\n\t" |
| + "movl %%ebx,%1\n\t" |
| "popl %%ebx\n\t" |
| - : "=a"(cpuid_data[0]), "=b"(cpuid_data[1]), "=c"(cpuid_data[2]), "=d"(cpuid_data[3]) |
| + : "=a"(cpuid_data[0]), "=r"(cpuid_data[1]), "=c"(cpuid_data[2]), "=d"(cpuid_data[3]) |
| : |
| : "cc" |
| ); |
| -- |
| 2.1.2 |
| |