diff options
Diffstat (limited to 'main/libc0.9.32/uclibc-libm-pic.patch')
| -rw-r--r-- | main/libc0.9.32/uclibc-libm-pic.patch | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/main/libc0.9.32/uclibc-libm-pic.patch b/main/libc0.9.32/uclibc-libm-pic.patch new file mode 100644 index 0000000000..ad87b78b24 --- /dev/null +++ b/main/libc0.9.32/uclibc-libm-pic.patch @@ -0,0 +1,67 @@ +GCC can emit prologue/epilogue code for the functions in various +different cases: + - frame pointers + - PIC build (to load ebx for indirect calls/jumps) + - forced stack smashing protection + +If we used jump in such cases, we'd corrupt the call stack and +crash. + +Signed-off-by: Timo Teräs <timo.teras at iki.fi> +--- + libm/ldouble_wrappers.c | 12 +++++++----- + 1 files changed, 7 insertions(+), 5 deletions(-) + +diff --git a/libm/ldouble_wrappers.c b/libm/ldouble_wrappers.c +index 7d5af90..5b424dc 100644 +--- a/libm/ldouble_wrappers.c ++++ b/libm/ldouble_wrappers.c +@@ -60,7 +60,9 @@ long long func##l(long double x) \ + * The return value is returned in st(0) per ABI in both cases (returning + * a long double or returning a double). So we can simply jump to func. + * Using __GI_func in jump to make optimized intra-library jump. +- * gcc will still generate a useless "ret" after asm. Oh well... ++ * ++ * We do need to use call (instead of tail jump) as gcc can create ++ * stack frame, and push/modify/pop ebx during PIC build. + */ + # define WRAPPER1(func) \ + long double func##l(long double x) \ +@@ -69,7 +71,7 @@ long double func##l(long double x) \ + __asm ( \ + " fldt %1\n" \ + " fstpl %1\n" \ +- " jmp " __stringify(__GI_##func) "\n" \ ++ " call " __stringify(__GI_##func) "\n" \ + : "=t" (st_top) \ + : "m" (x) \ + ); \ +@@ -82,7 +84,7 @@ int func##l(long double x) \ + __asm ( \ + " fldt %1\n" \ + " fstpl %1\n" \ +- " jmp " __stringify(__GI_##func) "\n" \ ++ " call " __stringify(__GI_##func) "\n" \ + : "=a" (ret) \ + : "m" (x) \ + ); \ +@@ -95,7 +97,7 @@ long func##l(long double x) \ + __asm ( \ + " fldt %1\n" \ + " fstpl %1\n" \ +- " jmp " __stringify(__GI_##func) "\n" \ ++ " call " __stringify(__GI_##func) "\n" \ + : "=a" (ret) \ + : "m" (x) \ + ); \ +@@ -108,7 +110,7 @@ long long func##l(long double x) \ + __asm ( \ + " fldt %1\n" \ + " fstpl %1\n" \ +- " jmp " __stringify(__GI_##func) "\n" \ ++ " call " __stringify(__GI_##func) "\n" \ + : "=A" (ret) \ + : "m" (x) \ + ); \ +-- +1.7.0.4 |