path: root/src/stdio
diff options
authorRich Felker <>2013-08-02 19:34:22 -0400
committerRich Felker <>2013-08-02 19:34:22 -0400
commit86cc54b577f445da1582d2cf1ac3eff064ca27ef (patch)
tree6e97212567048708456eb035e920fb92fd42f7c8 /src/stdio
parent2f820f3b1f639fee30f5bfa31aa3191758573f25 (diff)
protect against long double type mismatches (mainly powerpc for now)
check in configure to be polite (failing early if we're going to fail) and in vfprintf.c since that is the point at which a mismatching type would be extremely dangerous.
Diffstat (limited to 'src/stdio')
1 files changed, 7 insertions, 0 deletions
diff --git a/src/stdio/vfprintf.c b/src/stdio/vfprintf.c
index 1e7e6a47..a2b287bd 100644
--- a/src/stdio/vfprintf.c
+++ b/src/stdio/vfprintf.c
@@ -198,6 +198,13 @@ static char *fmt_u(uintmax_t x, char *s)
return s;
+/* Do not override this check. The floating point printing code below
+ * depends on the float.h constants being right. If they are wrong, it
+ * may overflow the stack. */
+#if LDBL_MANT_DIG == 53
+typedef char compiler_defines_long_double_incorrectly[9-(int)sizeof(long double)];
static int fmt_fp(FILE *f, long double y, int w, int p, int fl, int t)
uint32_t big[(LDBL_MAX_EXP+LDBL_MANT_DIG)/9+1];